Strange behaviour on modded X800Pro !

danx

My softmodded ATI X800Pro card works nicely with 16pipes and at XT PE speeds+.

But sometimes when I try to change the GPU or memory clocks by ONLY 1 MHz I get a corrupted screen/artifacts and have to do a reboot.

It also happens when I lower the clock speeds by one MHz increments.
( underclock to speeds below XT/PRO whatever )

I'm not looking for a O'C, I'm simply curious to know why !?

If I'm "lucky" I'm able to set it up to 542/583 without it crapping out.
And it runs stable at those speeds (no artifacts).
So it can't be that PE speeds are too much for it.

Does anyone have a clue to why it behaves like this ?

It runs without any artifacts for hours and with full AA / AF with ATITOOL.
(at "stock" 520/560MHz and higher once it "gets" there)
And no problems in any games.

But I'd really like to know why it sometimes cant handle ANY changes to the clocks ( GPU/MEM ) ??
Neither increases or decreases !

I flashed it using the "gigabyte" method first, but have since then flashed it with a modified flashroom.exe that flashes the "whole" BIOS memory area regardless (works very well and it's easier than the gigabyte method).
Didn't help though..

I've also tried 3 different bios versions, all compatible with my 1.6 samsung memory modules, just to see if it helped.
No change whatsoever though.

Any clues guys ?

Zebra

Probably needs the pencil volt mod. Otherwise, just leave it as is.

danx

Thanks, I was thinking about that too.