When I installed the VIA 4in1 driver pack 2 things happened: My CD-rom would disappear from the system and my HDD got way slower. It was like half the performance compared to the built in drivers in Win98 (checked it with Sisoft Sandra). I uninstalled it and then everything was fine (to uninstall, run the installation again).
MSI K7PRO, Win98 (not SE) IBM and Seagate HDD:s, Samsung CD-rom.
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You are ofcourse right brijesh33, I must have been confused. The one I installed was AMD:s driver pack 1.00. Sorry about that.
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