As I understand it, never had time to dig into it...
If the system has one of the faster ATA interfaces that require a 80 pin cable (ATA 100 and 133. Maybe some ATA 66) and you use a 40 pin cable, the system actually knows you've done this and slows the HD interface down to prevent data errors. (There are utilities that actually tell you which cable is in use on many of these systems.) That will slow pretty much the whole machine any time there is disk I/O.
The 80 wire cable is likely bad. They are easy to damage as the wire is only slightly larger than a few hairs. I've seen a couple guys swap cables and all were bad because they pulled on the wire when unplugging them. Many of them have pull tabs, use them. It will save the wire from damage.
The 80 wire cable shouldn't effect Win98 or any other OS. I would recomend you look up the disk interface specs for that system board and make sure you have the right cable for maximum performance.
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