Here is a good introduction to testing PC's. It also includes addresses of outfits that supply software that tests PC's.
This is from CURRENTS (Feb. 3).
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But the PC and its software are not immune to the year 2000 bug. Your PC may trip on January 1, 2000, because of a flaw in a clock chip, BIOS, operating system, application, or your data, or any combination of these factors. For a PC to be fully 2000 compliant--to properly recognize and calculate dates after December 31, 1999--every link in the chain must be compliant. If the system clock feeds the wrong date to the BIOS, the BIOS will pass it along to the operating system, which in turn will hand it to any application that asks for it, which in turn will use the wrong date information in spreadsheets and databases and financial programs. Even if the clock chip and BIOS are 2000 compliant, if the OS or an application isn't, you will still face the same problem.
Fixing the PC's Clock
The original PC, XT, and their clones didn't have clock chips. When one of these venerable systems booted up, you had to supply the date and time. But the ATs, 386s, 486s, and Pentium systems that followed came with battery-powered CMOS chips that not only stored system information (like drive type) but also included a real-time clock and calendar chip. The problem is that older Pentium systems and most of the PCs that came before them used clock chips that only stored the last two digits of a year. Pentium PCs made in the last year or two shouldn't have this problem.