The Y2K Hardware Problem Affecting Many PCs

Copyright (c) 1997 Colin Wheeler. Reprinted by permission. First appeared in New Scientist magazine.

About the Y2K hardware problem in many PCs Overview of the problem Why this problem can occur: a technical description of PC BIOS problems Impacts of this problem: what can happen if your PCs are set to the wrong date Finding Y2K hardware problems in your PCs Option 1: Check with your PC vendor(s) Option 2: Perform manual testing Option 3: Use software tools to perform automated testing Resolving PC Y2K hardware problems before they occur Option 1: Use an up-to-date PC with an already-compliant BIOS chip Option 2: Retire your older, non-compliant PC Option 3: Let your PC's operating system correct the date Option 4: Install a small piece of software to correct the date Option 5: Manually reset your PC's date Option 6: Synchronize your computer's date over the network Option 7: "Flash" your computer's non-compliant BIOS chip Option 8: Install a BIOS upgrade card Option 9: Replace an older PC with a newer, Y2K compliant PC Option 10: Remove and replace your PC's BIOS chip, RTC chip, and/or motherboard When your PC's date goes "blooey": correcting PC Y2K hardware problems after they occur Some other important Y2K issues affecting PC hardware Nearly all PCs' real-time clocks (RTCs) fail Y2K tests. Does this matter? Are there BIOSes which can't retain dates in the year 2000 and beyond? Are there BIOSes which don't properly recognize the year 2000 as a leap year? What is the "Crouch Echlin" (or "TD" or "time dilation") effect?

Overview of the problem: About the Y2K hardware problem in many PCs

Many "industry-standard" (also known as "Intel-based" or "IBM-compatible") PCs have a hardware problem that will prevent their internal clocks from rolling over from 1999 to 2000. When the Year 2000 arrives, the clocks in these PCs may instead revert to a date in 1980, 1984, or some other year.

Most PCs manufactured in 1996 or earlier have this problem. In addition, progressively smaller percentages of PCs built in 1997 and 1998 may also have this problem.

If you or your department has a PC whose Y2K hardware problem has not been resolved by the end of 1999, you might observe several different types of effects:

If your PC is powered on at midnight on December 31, 1999:

• Its clock may "roll over" correctly to January 1, 2000, but will revert to an incorrect year the next time that you reboot your PC or turn your PC off and on.
  
  or
  
  
• Its clock may fail to "roll over" correctly, and will immediately revert to an incorrect year.

If your PC is turned off before midnight on December 31, 1999:

• Its clock may revert to an incorrect year the first time that it is powered on during the year 2000.

What this problem means to you

If you don't correct the problem on a non-compliant PC, and thus it reverts to an incorrect year when the year 2000 arrives, in many cases this will have relatively minor impacts . A few application programs, however, could be moderately to severely affected by an incorrect date, so it is generally recommended that you find and resolve this problem before the year 2000.

How you can resolve this problem

If you have a non-compliant PC, its Y2K hardware problem can be effectively resolved "after the fact" - on or after January 1, 2000 - simply by manually resetting its system date. There are also a variety of methods you can use to resolve this problem on a personal or departmental PC before the year 2000 arrives.

What percentage of PCs may have this problem? [Karl] Feilder ... chief executive of the London-based consultancy Greenwich Mean Time ... found from a random sample of 500 personal computers of different brand names that 93 per cent made before 1997 [... failed to successfully transition into the year 2000] when their internal clocks were rolled over to the year 2000. More worrying, 47 per cent of those manufactured in the first half of 1997 failed their Y2K test, while 21 per cent of those made in the second half of 1997 also failed - as did 11 per cent of desktops made in the first half of 1998. John Macleay, Mainframe rush leaves PCs in peril , The Australian, October 6, 1998.

Why this problem can occur: a technical description of PC BIOS problems

The following is a fairly technical discussion. While it is helpful to know why this problem occurs, having an in-depth understanding of its cause is not essential to finding or resolving it.

The core technical issue in most PCs which have this problem is straightforward. When the year 2000 arrives, after a PC's internal clock chip (Real-time Clock, or "RTC") rolls over the year (much like the digits on a car odometer) from "99" to "00", a second multipurpose internal chip (Basic Input/Output System, or "BIOS") is responsible for noticing this and doing two things:

1. Rolling over a separate century counter - which is stored in a battery-backed area of memory called "CMOS-RAM" - from "19" to "20".
   
   
2. Providing the correct date (in the year 2000 and later) to any operating systems and/or application programs which request it.

The BIOS chips in most PCs manufactured in 1996 and earlier fail to perform these simple tasks, however. Even the BIOSes in some PCs built as late as 1997 and 1998 can't do so, thus leaving the PC's internal hardware clock set at "1900". (As noted below, the BIOS's interaction with operating system software can later cause your PC's internal clock to be set to a different, incorrect year, such as 1980 or 1984.)

PCs with older, non-Y2K compliant BIOS chips fall into two categories:

• PCs with non-compliant BIOSes that can be helped to successfully transition to the year 2000 and beyond.
  
  In the case of nearly every PC with a non-compliant BIOS, a simple no-cost procedure - manually resetting its date just once, on or after January 1, 2000 - will effectively resolve its Y2K hardware problem. After doing so, your PC should continue to use the correct dates throughout the year 2000 and beyond.
  
  In addition, you can select from a number of other methods for resolving a PC's hardware Y2K problem before the year 2000 arrives.
  
  
• PCs with extremely non-compliant BIOSes.
  
  A very small number - estimated at perhaps less than 0.1% - of PCs have extremely non-compliant BIOSes which simply can't retain dates in the year 2000 and beyond . As described below, these PCs present special challenges.

PCs with newer, Y2K compliant BIOS chips are not subject to this problem. These newer BIOS chips contain updated logic which instructs them, when they notice that the internal clock chip (RTC) has rolled over the two-digit year value to "00", to know that this represents the year "2000", not "1900", and thus return the correct date to operating systems and applications. (BIOSes will typically first notice that a PC's two-digit year has rolled over to "00" when a trigger event occurs, such as a 'get date' or 'set date' request from an operating system or an application program, or when the PC is turned on or rebooted.)

The updated logic in most or all newer, Y2K compliant BIOS chips will also instruct these chips to nudge the PC's century counter over from "19" to "20", thus providing the correct century to any software which might read this counter directly. (This century counter is stored in a battery-backed up area of memory called "CMOS-RAM.")

More broadly, the logic programmed into newer Y2K compliant BIOSes specifies that, if the PC's two-digit year falls below "80", the current year should be regarded as falling within the range from 2000 through 2079, rather than the range from 1900 through 1979. Thus, the two-digit year value "00" would represent the year "2000", "01" would represent "2001", and "79" would represent "2079". (Because 1980 was the earliest year supported by the IBM PC, the two-digit year "80" is the lowest year that such newer BIOSes regard as falling within the 1900s, rather than the 2000s.)

How "1900" can be changed to "1980" or "1984", or
how PC operating systems handle inaccurate dates from the PC's hardware

When a PC is powered on or rebooted, some PC operating systems (OSes), request the current date from the BIOS chip. When certain of these operating systems are handed the invalid year "1900" by a non-compliant BIOS chip, they will change it to the earliest date they know about. In many cases, this will be a date in 1980; in some cases, it might be a date in 1984 or some other year. (January 1, 1980 and January 4, 1980 are particularly common modified dates you might encounter on PCs whose BIOS problems have not been resolved, and which are running DOS and other OSes based on DOS such as Windows 3.x and Windows 95.)

Some other operating systems don't get the current date from the BIOS chip when a PC starts up. Instead, they bypass the BIOS and directly read the two-digit year value (e.g. "00") from the clock chip (RTC). Some OSes may also get the current date by combining this two-digit year with the century counter (e.g. "19" or "20") stored in the PC's non-volatile memory (CMOS-RAM). By using either of these methods, an operating system could potentially end up using the year "1900" on a non-compliant PC.

Fortunately, some newer PC operating systems such as Windows NT 4.0 and Linux, which bypass the BIOS to obtain their dates directly from the PC's clock chip (RTC), have date correction logic analogous to that used by newer, Y2K compliant BIOS chips (above). These operating systems will interpret an RTC date of "1900" as representing the year 2000, "1901" as 2001, and so on.

More information If you're technically inclined and curious about this problem, you might enjoy reading some of the in-depth technical descriptions below: Pete Woytovech, Dell Computer Corporation, VECTORS: The Century Rollover and the PC System Date Intel Corporation, Year 2000 Information and General Comments on Intel Components The MITRE Corporation, Time and Date on Your Personal Computer

Impacts of this problem: what can happen if your PCs are set to the wrong date

The impacts on your key functions of having a PC set to a date in 1980, 1984, or some other year, when the actual calendar year is 2000 or higher, can vary widely - from trivial to serious - depending on what operating system and application programs are being used on that PC.

Undoubtedly, many of these impacts are likely to be minor, sometimes even trivial. As an example, some word processing programs offer an option to insert the current date into a document's header, footer, or body. If you use this option, and your PC reverts to an invalid date, the dates on your printed memos, letters, or papers might be inaccurate, unless you notice this and manually correct these dates.

However, some impacts which might initially seem minor could potentially have unexpected repercussions. For example, if your PC's system date were to revert to an invalid year, the Date: field in your outgoing e-mail messages might potentially be set to a day in 1980 or 1984 or some other past year.

In many cases, this might simply represent a cosmetic display problem. However, if your messages were received by correspondents whose "In" or "Inbox" mailboxes are sorted by date, and which already contained tens or hundreds of other messages bearing more recent dates, they might be sorted out of sequence and your correspondents might fail to notice your e-mail messages.

Finally, the impact of an incorrect PC system date on certain applications could potentially be serious. For example, some programs are configured to delete ("purge") old files. If, as a result of a PC's date reverting to a year such as 1980, then later having been corrected to the year 2000, a few files might be marked as having been created or last modified 20 years in the past, it's possible that these files might be at risk of being be purged.

A sampling of some of the other types of problems that might result when a PC has reverted to an incorrect system date include:

• Files being marked with incorrect creation and/or modification dates.
  
  This could potentially have implications for both programs and humans when trying to determine which of the successive revisions of a file is newer. One particular area of concern are certain programs which may perform backup, restoring, copying, moving, or archiving of files based on these dates.
  
  A related concern are utility programs, such as the popular Norton Utilities, which are capable of detecting files with invalid dates. If your PC's date has reverted to 1980, for example, such a program might identify your files validly created in later years as bearing invalid dates, and may offer to "correct" them for you.
  
  
• Invalid date/time stamping for transactions or data sampling.
  
  Database records, text files, and the like are often used to store the dates and times when certain actions took place. If your PC's system date is incorrect, these date/time 'stamps' might be inaccurate. This could affect financial transactions, samplings taken of data from scientific experiments, and the like.
  
  
• Incorrect calculations based on the current date.
  
  Some programs use the current date when performing certain calculations, such as comparing dates, computing the duration between dates, and identifying the day of the week. If your PC's current date is incorrect, calculations based directly or indirectly on the current date will generate inaccurate results.
  
  As an example, some spreadsheets, databases, and other such programs offer functions - such as Microsoft Excel's TODAY() and NOW() - that return the current date. If some of your formulas, macros, modules, scripts, or programs rely on the current date returned by such functions, and your PC's date is incorrect, they will generate inaccurate results.
  
  
• Security methods failing due to lack of date and time synchronization with other computers.
  
  Some methods of identifying yourself to another system (authentication), or of indicating what resources you're eligible to access (authorization) might depend on the date and time at your PC being synchronized with the date and time of another computer elsewhere on a network. If so, and if your PC has reverted to an incorrect date, some of these methods might fail.
  
  
• Expiration of software and passwords.
  
  Although PCs with invalid dates set into the future are more likely to cause problems resulting in expiration of software licenses (whether hard-coded into programs or auxiliary files, or stored in a license or launch-metering server), time-expiring demo or evaluation programs, time-limited passwords, Web browser "cookies," and the like, having your PC set to an incorrect date in the past could also conceivably trigger such problems.
  
  Problems resulting in expiration of software, passwords, and the like might also potentially occur if your PC is allowed to revert to an earlier year and you then reset its date to the year 2000 or beyond.
  
  
• Improper scheduling of times to run automated processes
  
  If you've set up schedules to run various programs at certain dates and times, shifts in your computer's system date - whether backwards or forwards - can cause processes to be run at unintended times or to be inadvertently skipped.
  
  
• Creation of filenames containing incorrect dates.
  
  Some applications - typically custom-written programs - may create files whose names contain a representation of the current date, such as DB990516.DAT. If these applications make assumptions about how to process data based on the names of these files, and some of their files were created when your PC's date was incorrect, this could lead to a variety of problems.

As a result, it's usually very desirable to resolve this problem before the year 2000 arrives. In addition, if your PC does happen to revert to an incorrect year, we recommend that you reset it to the current date immediately upon noticing this problem.

Option 1: Check with your PC vendor(s)

Most vendors of "name brand" PCs provide detailed information on their Web sites that can help you determine which of these vendors' PCs might have Y2K hardware problems.

The following is a sampling of some PC vendors' Web sites that provide Y2K compliance information for their products:

Compaq (includes compliance information for DIGITAL Equipment Corporation [DEC] PCs)
Dell
Gateway
Hewlett-Packard
IBM
Micron Electronics
Toshiba

Representative pages which list additional PC vendors' Web sites include:

Intel's Hardware and Software Vendor Sites page
Y2KBase.com's "PC Systems" page

You'll need to decide whether you are confident relying exclusively on vendors' assurances about the hardware Y2K compliance of their PCs, especially on your mission-critical PCs. If not, you'll want to conduct your own testing.

If you discover that your PC has a Y2K hardware problem, your vendor's Web site may also provide suggestions and tools for resolving this problem. For instance, the vendor might provide downloadable software to "flash" your computer's non-compliant BIOS chip or "TSR" or "device driver" software that your PC can load each time it starts up in order to correct your computer's date .

Option 2: Conduct manual testing

If you have a large number of PCs, it is often faster and easier to use software tools to check their BIOSes for Y2K hardware problems. Because of the possibility of human error when conducting manual tests, the best testing tools may also enhance the probability that you'll obtain accurate test results.

However, there may be circumstances where you may wish to conduct manual testing, particularly if you're just responsible for testing a single PC.

If you choose to manually test a PC's BIOS, we recommend that you do the following:

• Create a bootable DOS system diskette and use it to start up your PC.
  
  Every PC, even one which is running a recent, powerful operating system such as Windows NT, Linux, and OS/2 Warp, is also capable of starting up from a system diskette containing the venerable DOS operating system.
  
  Making a Startup Diskette for a PC describes how to make such a bootable DOS diskette.
  
  Why do this? As Fred Langa explains in his Windows magazine article Are You Ready for 2000? :
  

  ... you need to run all the tests from a DOS command line. That's because you need to see the results in as raw and unfiltered a fashion as possible. You don't want Windows' higher functions correcting or altering these results. Also, [this helps you avoid potential problems from changing your PC's system date:] you might have time-dependent Windows applications that run at set intervals, or you may even have time-limited software licenses [or passwords] that will expire if you change the system date to the future.

  For this very reason, many of the software tools for checking your PC's BIOS are either provided on a bootable DOS diskette or their vendors recommend that they be run from DOS.
  
  
• Reset your PC's date when you're done.
  
  Be sure to set your PC's system date back to the current date before removing the DOS startup disk and rebooting your computer. This way, you won't boot your PC into Windows (or another operating system) with an incorrect system date, which could potentially have some deleterious impacts on some applications.

A number of articles on the Web and in popular computer magazines provide step-by-step instructions for manual tests you can perform to determine which of your PCs might have non-compliant BIOSes. Three representative examples are presented below:

• The PCY2000 Alliance's PC ON/OFF Tests .
  
  Procedures for three simple manual tests. These were prepared by the PCY2000 Alliance , a consortium of PC manufacturers including Compaq, Dell, Hewlett Packard, IBM, and Toshiba.
  
  
• Cade Metz, Testing Your PC Hardware , PC Magazine, October 6, 1998.
  
  A single test (with a second optional test, under the subhead "Other Possible Glitches," which we recommend you also perform) that should detect most BIOS problems.
  
  
• Fred Langa, Are You Ready for 2000? , Windows Magazine Online, January 1, 1999.
  
  A sequence of five tests that can help you pinpoint exactly what Y2K hardware problem(s) might affect your PC.

Option 3: Use software tools to perform automated testing

Software Tools for Finding & Resolving Y2K Problems lists several software tools that you can use to automate the process of testing your PCs' BIOSes for Y2K hardware problems.

When using such tools, you should be aware that the terminology they use to name their tests and report their testing results has not been standardized. In some cases, two tools might use a different name to describe what is essentially the same test.

In addition, the numbers and types of tests they perform may vary widely between tools. And some tools may include probably meaningless tests of the PC's real-time clock (RTC) and of the PC's rollover behavior during leap years in the year 2000 and beyond.

In nearly all situations, you'll probably want your testing tool to accurately tell you just three things about a PC:

• If this PC is powered on at midnight on December 31, 1999, will it properly roll over - in real time - to January 1, 2000?
  
  
• If this PC is turned off at midnight on December 31, 1999, will it start up with the correct date when it is first powered on - whether on January 1, 2000 or thereafter?
  
  
• If this this PC is rebooted or power-cycled on or after January 1, 2000 - will it keep (retain) the current date ?

You will need to pay special attention to the tool's documentation to determine which of its test results will give you answers to these three - and just these three - key questions. In many cases, the other results your tool might report will be essentially irrelevant.

Two of these tools merit special discussion. Both are widely-used and available for many types of uses at no cost:

• Test2000
  
  RighTime's TEST2000 is among the most highly-regarded PC BIOS Y2K testing tools.
  
  RighTime also offers a no-cost companion tool to TEST2000, called "ViewCMOS", which "dynamically displays the contents of CMOS RAM and the three PC clock sources." This way, you can see exactly what is happening inside your PC during various rollover scenarios without the 'filtering' of a testing tool's results.
  
  In addition to being downloadable from RighTime's Web site, Test2000 is also 'bundled' with Greenwich Mean Time's Check 2000 Client Server , a commercial "tools suite" which integrates a set of different tools for checking various Y2K problems on PCs.
  
  
• YMARK2000
  
  NSTL's YMARK2000 is another widely-used, well-regarded testing tool. COMPAQ, Dell, and Gateway are among the major PC vendors which use YMARK2000 to test and certify their recent PCs' hardware as Y2K compliant.
  
  This tool, by design, incorporates a significant omission. It doesn't automatically perform a reboot test, although under some circumstances it may recommend that you perform one manually. (Instructions on how to do so are provided in the YMARK2000 FAQ .)
  
  A reboot test is necessary to identify those few PCs with extremely problematic BIOSes which can't retain dates in the year 2000 and beyond . NSTL flatly states in its Frequently Asked Questions document that the reason for not including this test is that "Implementing a reboot test in a free product would be prohibitively expensive."
  
  The Center for Academic Computing at Pennsylvania State University has prepared a detailed guide to using YMARK2000 to test PC BIOSes, Testing Your PC BIOS for Year 2000 Readiness , which could prove helpful, at least as a starting point, for those wishing to use this tool at UC Berkeley.

With many of these testing tools, you'll need to start your PC from a bootable DOS diskette, and then run the testing software from that diskette. Making a Startup Diskette for a PC describes how to make such a bootable DOS diskette onto which you can then copy the testing software. (Some testing tools may already come on a bootable diskette, or may include an installation process which automatically creates such a diskette and copies the testing software onto the diskette.)

Some consultants and in-house support providers recommend that you use two or more different software tools to test each PC, particularly in the case of mission-critical PCs.

A PC with an incorrect system date - even one which goes uncorrected for just a day or two - can potentially result in some deleterious impacts for your applications and operating system. Most of these will likely be trivial, but a few - on some of your PCs - could be moderate to serious in their effects. For this reason, it is better to prevent your PCs from reverting to incorrect dates than to manually reset these dates later on.

The following are ten different ways that you might resolve your PCs' Y2K hardware problems by preventing PCs with non-compliant BIOSes from reverting to an incorrect year. Each has its particular advantages, limitations, and disadvantages.

If you're responsible for resolving this problem on a single personally-owned PC, it's likely you can select a single method of resolving this problem from the list below.

The following methods are listed in order by the approximate amount of time and effort they will require to implement. The methods that we believe are most easily implemented are listed first:

Option 7: "Flash" your computer's non-compliant BIOS chip Many newer PCs have BIOS chips whose programming code is stored in a "Flash" memory chip. These chips can be 'reprogrammed' by downloading new software into the memory chip. (Technically, a "Flash" memory chip is a type of programmable read-only memory, or "PROM," chip, which can be bulk-erased and its contents rewritten.) Many PC, motherboard, and BIOS chip vendors have newer software that you can download into your PC's Flash BIOS chip that incorporates date correction logic, making your PC Y2K hardware compliant. Typically, you can begin the process of "Flashing" your BIOS - a commonly-used, colloquial term for this process - by going to your PC vendor's Web site , identifying your specific PC model (and sometimes also your PC's specific make and model of BIOS chip), and downloading a small software program to a diskette. You can then run this program to update the software in your PC's Flash BIOS chip. If you have a "clone" PC that you or a system integrator or reseller put together from various components, you may need to visit the Web site of your motherboard or BIOS maker, rather than your PC manufacturer, to determine which Flash BIOS update is required for your PC. The computing support staff of our sister campus, the University of California, Davis, offer useful information for those who may wish to resolve their PC Y2K hardware problems by flashing the BIOS or installing a BIOS extension card. You can view the slide presentation from UC Davis's PC BIOS training session of November 3, 1999 . Advantages Once a PC's BIOS is "flashed" with new, Y2K-compliant BIOS code, the PC then becomes Y2K hardware compliant. You can typically obtain software to "flash" BIOSes for Y2K compliance at no cost from your PC, motherboard, or BIOS vendor. Upgrading a Flash BIOS for Y2K compliance may concurrently add support for other new hardware features, such as larger hard disk volumes; booting from removable drives, such as Zip drives; and expanded video capabilities. Disadvantages & limitations If anything goes wrong during the BIOS upgrading process, you can effectively make your PC unusable. For example, if the power to your PC is interrupted during this process, or the "Flashing" process itself is interrupted due to any other cause, this can result in an erased or incompletely updated BIOS, which makes your PC effectively unusable. Only some newer PCs have Flash BIOS chips. If your PC doesn't have this type of BIOS, you'll need to use some other method to resolve its Y2K hardware problems. You'll need to use special care to exactly match your PC, motherboard, and/or BIOS model with the downloadable software update prepared for your specific "Flash" BIOS chip. Finding the correct Flash BIOS upgrade for your PC can sometimes be time-consuming.

Option 10: Remove and replace your PC's BIOS chip, RTC chip, and/or motherboard This option is only for those with a high degree of technical proficiency with PC hardware. If you have a PC which is not Y2K hardware compliant, one option - short of replacing the entire computer, is to physically replace either a PC's BIOS chip - if that chip is socketed and thus can be removed - or the PC's entire main printed circuit board ("motherboard"). A very few special PC motherboards may also have the correct type of socket to accommodate a special Y2K compliant Real-time clock (RTC) chip from Dallas Semiconductor. An example of a company which sells replacement BIOS chips is Micro Firmware, Inc. . Advantages Installing a new BIOS or motherboard may add new features and enhance a PC's performance. Disadvantages Once again, this option is only for those with a high degree of technical proficiency with PC hardware. Typically, installing a new BIOS chip or PC motherboard requires considerable technical expertise. Performing this task, as well as troubleshooting any resultant problems, can also be very time consuming. New BIOS chips typically cost in the neighborhood of $50, and new motherboards typically cost $150 and up. You'll need to make sure that the BIOS chip you're installing is compatible with the motherboard on which it is placed, or that the motherboard you're installing is compatible with all of your PC's other vital components, such as (to name one example) its ATA or SCSI disk drives.

If, on or after January 1, 2000, the dates on one or more of your PCs revert to an incorrect year as a result of a problem with a non-Y2K compliant BIOS chip, you just need to manually reset their dates - once - to the correct date.

This fact should be repeated and emphasized: the Y2K hardware problems affecting nearly all non-compliant PCs can be effectively corrected, after they occur, just by manually resetting their incorrect system dates once. This makes these PCs' hardware effectively Y2K compliant from then-on!

A very small number of PCs have extremely non-compliant BIOSes which simply can't retain dates in the year 2000 and beyond . As described below, these PCs present special challenges.

If your PC doesn't have one of these extremely non-compliant BIOSes, but still can't retain the date that you've set, it's possible that its battery that maintains the date and time and some other settings might be low or dead.

Nearly all PCs' real-time clocks (RTCs) fail Y2K tests. Does this matter?

When you run use software tools to perform Y2K diagnostic tests on a typical PC's hardware, if the tool includes real-time clock (RTC) tests, the PC is almost certain to fail one or more of these tests.

Should you be concerned? Probably not. By definition, in nearly all industry-standard PCs, the real-time clock cannot nudge the century counter over from "19" to "20" - this task is the responsibility of the BIOS, not the RTC - and so tests which check whether the RTC itself can properly roll over the PC's date from December 31, 1999 to January 1, 2000 will almost always fail.

As PC-maker Gateway notes in Personal Computer Clocks and Year 2000 Testing :

... some test software is being sold that will report that a PC is not Year 2000 compliant, even if it passes NSTL's YMARK2000 test [and other BIOS tests]. However, of the software tests that Gateway has examined, all use unconventional methods to check date compliance. They ignore the date correction logic found in the BIOS and check the RTC date directly. For any PC based on the IBM AT standards, this testing method practically guarantees a 'failing result.' Contrary to these tests, Gateway's evaluation of commercial software applications found that they do not access date information via the RTC.

(The exceptions to the above description are a tiny handful of PCs with certain Dallas Semiconductor real-time clocks that will nudge over their own, on-board century counter from "19" to "20" without requiring assistance from a BIOS chip. These Y2K compliant RTC chips cannot be installed on most PC motherboards, however.)

What really matters is how your programs get the current date. Nearly all "real life" application programs access the date by requesting it from a PC's operating system or from the BIOS, not by going around the OS and BIOS to directly access the date values maintained by the real-time clock.

The remaining concern, then, is that a few custom-written programs might directly obtain the current date from a PC's real-time clock, either reading only the RTC's two-digit year value (e.g. "00") or adding this value to an uncorrected century counter ("19"), and thus derive an incorrect date. However, as the quotes below demonstrate, there is still some controversy and speculation about whether any such programs exist. (It is certain that some operating systems, such as Windows NT, do access the real-time clock directly, but these OSes often incorporate their own date correction logic, and some of these OSes prevent application programs from accessing the RTC directly.)

If you do identify that you have one of the rare custom applications which accesses the date from the RTC, and you absolutely need to use this application and can't reasonably fix or replace it, there may be some workarounds available in the form of software fixes. Some of these fixes are sold commercially by third-party vendors, while others may be available at no cost from major PC vendors for their branded PCs. For instance, Dell offers a device driver for PCs running DOS and Windows 3.x/95/98 (and a corresponding native program for Windows NT), the Y2000RTC Driver which automatically updates the century counter without intervention by the BIOS, and Compaq offers a similar Year 2000 Device Driver for PCs running DOS and Windows 3.x/95/98.

Are there BIOSes which can't retain dates in the year 2000 and beyond?

Yes. There are a very small number of PCs - perhaps less than 0.1% - which have extremely problematic BIOS chips which cannot retain dates in the year 2000 or beyond.

With nearly all PCs that revert to incorrect dates when the year 2000 arrives, you have a simple fallback: just manually reset their dates to the current date. You should only need to do this once for each of your PCs. Your PCs should then work fine, continuing to retain the correct date and time throughout the year 2000 and beyond.

However, a few PCs have extremely problematic BIOS chips. When - during the year 2000 or later - you reboot a PC containing one of these BIOSes (by pressing the Control-Alt-Delete keys or the PC's reset button), or when you turn it off and on, you may find that the PC cannot retain the date that you've just set. Instead, it will again revert to an incorrect year.

Two older Award BIOSes can't retain dates in the year 2000 or beyond

We're currently aware of only two problematic BIOS chips which can't retain dates in the year 2000 or beyond. Both are older versions of Award BIOSes. Award BIOSes are found in a large percentage of industry-standard PCs, and only these two specific BIOS versions have been found to have a serious Y2K hardware problem. In fact, many of the newest Award BIOSes are completely Y2K compliant.

Award is now a Phoenix Technologies company. When we last checked on September 27, 1999, Phoenix provided only limited information about Y2K compliance issues in Award BIOSes. As a result, some of what we know of these BIOSes comes from third-party reports, which might not be completely accurate:

According to Phoenix's Web site, problematic Award BIOS chips were manufactured from "September 26, 1994 to April 19, 1995," although Phoenix has "recently discovered that the possible Award BIOS non-compliance date range may extend to dates after April 19, 1995." A later Phoenix report lists the ending date as May 19, 1995. (Another, third-party report cites Award BIOSes manufactured between April 26, 1994 and May 31, 1995.) The problematic BIOS versions are 4.50g and 4.51g. (Some of these BIOSes may have been further modified by PC vendors, and might not always have these specific version designations. We've also seen reports that not all BIOS chips with these versions have this problem.) They were typically installed in PCs with 486 and early Pentium CPUs.

At the root of the problem is that these BIOSes recognize as valid only years in two limited ranges: from 1994 through 1999 and 2094 through 2099. (We've seen other reports where the starting point of the first 'valid year' range is said to be 1995 or 1996.) As a result, the years 2000, 2001, and so on are not recognized as valid by this BIOS.

Resolving Y2K problems with these older Award BIOSes

In late September 1999, Phoenix Technologies released a no-cost Phoenix PC Y2000 Test/Fix Tool, which includes a software fix for these problematic Award BIOSes. You can download this Tool from Phoenix's Phoenix PC Y2000 Test/Fix Tool page. (If this direct link to the Phoenix PC Y2000 Test/Fix Tool should later be moved or otherwise doesn't work, you can visit the vendor's Year 2000 Resource Center , which should provide a new link to this Tool.)

As an alternative to installing Phoenix's software solution, PCs containing one of these problematic BIOSes can also be retired from service; replaced with newer, Y2K compliant PCs; or have their BIOS chips (if socketed) or their entire motherboards removed and replaced .

Before Phoenix's software solution was released, Microsoft's white paper, Windows Operating System Interactions with BIOS and Real Time Clock also suggested a no-cost workaround: adding a DATE command to the AUTOEXEC.BAT files (or equivalent startup scripts) on these computers, which would allow the correct date to be manually entered each time these computers start up. We suspect this would be inacceptably inconvenient for most campus PC users, however.

Are there BIOSes which don't properly recognize the year 2000 as a leap year?

None that we know of. This has been widely reported as a concern, and many software tools test for it. If a problem like this were not corrected, a PC's clock might roll over from February 28, 2000 to March 1, 2000, skipping the legitimate leap year date February 29, 2000, or other anomalous behavior might occur.

However, we have not yet seen any reports of anyone having seen this problem in "real world" tests of PCs.

What is the "Crouch Echlin" (or "TD" or "time dilation") Effect?

On boot up, after year 2000, the computer may occasionally make a jump in its date or time. For example, you have been running your computer every day since January 1, 2000. It is now January 9. ... Yesterday when you shut off your computer the date and time were correct. Today you start your computer, but it reports the date as April 17, 2000 ...

Engineers from Intel Corporation and Compaq Computer Corporation worked together to examine the Crouch Echlin effect. Their findings are described on their respective Web sites:

• Intel's Analysis of the Crouch-Echlin Effect
• Compaq's Year 2000 Compliance Program Frequently Asked Questions
  (The Crouch-Echlin Effect is addressed in the responses to questions 18 through 23 in this document.)

Neither Intel nor Compaq was able to duplicate this Effect in their own testing. And Intel noted (when we last checked their document above on June 23, 1999) that:

Intel has been unable to duplicate the "Crouch-Echlin" effect. We cannot confirm or deny the existence of this anomaly. We have tested all hypotheses asserted by Echlin, our customers and Intel experts and are confident that we have disproved all as root causes. We will continue to follow up on well-documented cases.

Nonetheless, based on the scattering of anecdotal reports of this Effect seen in various mailing lists and newsgroups, it is at least possible that some older PCs may infrequently exhibit a condition where their internal dates might 'leap' erratically when powered up. And a variety of new hypotheses continue to be advanced about why this Effect - if it ultimately is determined to be a valid phenomenon - might be occuring.

At this point, your best approach might be simply to observe that this Effect has been reported. If you're concerned about possible risks it might pose to your departmental PCs, you might also consider reducing these risks by migrating critical departmental functions off of your older PCs, which are claimed to be disproportionately susceptible to problems of this type.