???

[Anatoly]

I have Linux RH 7.2 and GeForce4 Ti4200 8x on KT400(Athlon XP 2100).
What driver must be downloaded(IA32,64,AMD...)?

[Kiamu]

since VIA KT400 afaik is a intel 32bit mobo and the AthlonXP is 32 bit too try the IA32 ;)

[bwkaz]

Yes, you need IA32.

With the KT400, though, you'll probably want to set the AGP rate to 4x (if it's 8x capable, and if your video card is too). There are quite a few issues with AGP 3.0 (AGP 8x) and the drivers; apparently not all the bugs are out of them yet. The latest official (as in non-prerelease) kernels also don't have support for the KT400's AGP chipset, but I believe 2.4.21-pre6 does.

[Kiamu]

yes, in the latest pe-kernel it is supported. at least a friend of mine told me that the last problems were solved for him with that kernel.