Overclocking 1.2 to 1.4 unstable - need advice

[VecchK]

Hello ladies and gentlemen. I'm the somewhat proud owner of an Abit KT7A motherboard and an AMD 1.2 Athlon. I've been toying with it for about two weeks now and I can't seem to get the bugger up to 1.4 GHz and keep her stable in 3d. I've tried 140 x 10 and 133 x 10.5, both crash after a few minutes of intense 3d and are otherwise stable. 1.33 GHz (140 x 9.5 and 133 x 10, currently at 140 x 9.5) is perfectly stable. I've tried upping my core voltage as high as the motherboard allows (1.85 which actually yields 1.92). I've disabled AGP 4x and fastwrites, and have tried all different sorts of aperture sizes for AGP. I've also played with all the different memory settings and got the same results. Anyone have any clue why I can't get it up to 1.4? Any advice is welcome.

Oh, the system, processor and video card are all nice and cool so I don't think it's a heat issue. My CPU at 1.4 maxes at 38c and i have an armada of fans on my mainboard, ram, cpu and video card.

[JRbob]

What temp is your prossor when your computer crashes

[VecchK]

I logged the temps during 3dmark2001 when it crashes and they're always 37 or 38.

[Ingo]

Two things:

Try less aggressive memory timings to see if that takes care of the problem.

Otherwise, even though it's a 400W Antec PS (unless it's the PP403X), it may not be adequate for your current system. See AMD recommeded PS listing: http://www1.amd.com/athlon/power

[el]

The power supply will be fine! unless he has 16case fans! try the memory settings and let us know how it goes! up the vcore and i/o voltage too. remember some chips just won't go so high without extreme cooling but your temps seems very low.

[VecchK]

I knocked the memory timings down to their most conservative settings and got the same results. The VCore voltage is at max. (1.85 in bios yields 1.92) My I/O voltage is only 3.2 but if I up that any more the VCore voltage starts to get closer to what I set it at and crashes even faster. IE, 1.85 and 3.2 yield a 1.92 VCore. 1.85 and 3.5 yield a 1.87 VCore. The lower the VCore voltage the faster it crashes, but it's wierd cause 1.85 should be more then enough for a 1.2 @ 1.4.

[VecchK]

I just checked my power supply. It's the PP403X.

[Ingo]

OK. Are you running Win2K? If it only happens during 3DMark 2001, try this:

http://support.microsoft.com/support/kb/articles/Q270/7/15.ASP

[VecchK]

Yup, running Win2k but I already put that patch in. Just checked to confirm that it was still in there and it is. This is driving me freaking bonkers. :) I'll keep playing with it. If anyone has any more suggestions or questions, keep them a'comin' :)