Ahh... I can make my first post in a thread that I know something about.. heh. Windows 95 does have problems with many CPU's higher than 350 MHz. (Windows Protection Error in IOS.VXD) However, Microsoft and AMD issued a fix for this (amdk6upd.exe - remember when K6-2 Super Socket 7's were the screaming processor? lol ) This patch fixes the problem with processors up to 2.1 GHz, where a second problem occurs. (Windows Protection Error in NDIS.VXD) I spent many hours trying to get around this problem. This problem also affects 98FE, and M$ issued a hotfix for 98FE. The hotfix will not work on Windows 95.. I tried pulling files out of it and installing them manually, etc etc, it did not work. Here's what happens: 95 will install properly, then on the reboot you will get the first (IOS) error. After patching this error, you will get the second one (NDIS). I tried copying versions of ndis.vxd from the 98FE hotfix and from 98SE and putting them into 95, but this was unsuccessful. Being exasperated at this point, I just went and deleted ndis.vxd and then it gave another error concerning nwredir.vxd so I deleted it as well. Then - lo and behold, it said those two files were missing, press a key to continue.. and 95 loaded up. Only one more error message was displayed, "The NetWare compatible shell is unavailable." then, 95 went happily about its business. All this was done on a 3.06 GHz P4 HT machine. So - other than networking functions, 95 will run on processors faster than 2.1GHz. Getting there is rough, and the lack of networking (dial up, broadband, etc) effectively kills a lot of usefulness; but it CAN be done. (I'll bet Rudolph Loew could fix it ) As far as I know, Windows 98 SE does not have a limit on the speed of processor it can use (or at least it hasn't been hit yet).