NIC cards?

[WoodPeckr]

you may have ran disk defrag but what about chkdsk or norton disk doctor?

also you may have had some program making backups and not automaitically deleting them after a certain time.

bad files or undeleted recovered files may have taken up the space.

Suspected something like this.
However I never ran chkdsk or norton disk doctor but did run disk cleanup and scandisk frequently with Win98.
Never ran a program making backups, just went with any default settings from Win98.
Because there it was only a 8.5 Gig HD and I needed the space, I made a habit of going through 'C' drive and dumping bad files or anything else not necessary that may have been accumulating on the C drive.

BTW since we're talking about dumping junk files that accumulate in your PC, here's a great little utility that cleans out things pretty well.
It works better than 'disk cleanup'.
It's about 1 meg, free, quick and cleans out both HD and registry.

Worth getting if you don't know about it:

www.CCleaner.com