I have a Tyan 1573 ATX board with a TX chip set and had an AMD K6-2/350 running on it today. It usually runs with a P5/233. The board is not supposed to work with K6 chips, but it did. The FSB only goes to 66 and the multipliers only to 3.5, but if you set the multiplier to 2, the 350 will "see" it as 6 and that makes it ~400 (66x6). The first time the computer posted, it showed the chip as a 486 at 66 (2x66), but SiSoft Sandra showed it as a K6 at 401. After the first post, the computer does not show any chip/chip speed, just all the other normal post stuff. Strange huh! I ran benchmarks with the 233 and the 350 (400), the K6 was FAR better. I ran the burn in program in Sandra for an hour and all was good. Also ran some games that work the system (or at least that I like)CFS and Motorhead and both worked great, no crashes and much higher FPS. BUT, then I decided to run the Prime95 program, and it kept saying that there were rounding off errors. This was the first time I had tried the program to "work" the system. So I guess there is something not quite right deep down somewhere.
Bottom line for me is that when my K6-3+/450 comes in this week for my one computer that currently has the 350, the 350 is going in the 233 machine. It runs all the MS Office software and the games I play without locking and Sandra shows that the improvements are real.
If anyone out there knows why Prime95 is finding an error when Sandra is not, please post!
Sorry this was so long, but I hope it helps.
Hugger1