but you need take note one thing, my previous assumption maybe wrong, now SB is well cooled down, but the system hang is still there, I realize it is no more a heat problem because all my parts are in good temp. So I try to minimize the problem to NB and AGP bus link, I try to adjust the ration to 8:2:1 instead of the fixed(66Mhz 33Mhz), after that, everything is fine, it is working!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Now I am testing the 285Mhz(3-4-4-8) with 8:2:1 at 72Mhz:36Mhz, it is fine. Previously, dxdiag and 3d mark03 or AquaMarks all hang at the first second @ this bandwidth. now all of them can pass the test. Since my cpu can not run @285*9 well. I decide change to 275(2.5-4-4-8) 275*9=2475Mhz now I can pass all the 3D tests. Cheers! At least I make some progress, I now understand the lock apg.pci of Abit is not functioning well. So when we run 3D demanding program, the MB will maybe switch between other different ratio in quite a short time---the driver confused and hanged. I feel my poor card can still work @ AGP=72Mhz, so i believe your king card can surely run without any errors now. As i recommend, you can try 285*9 in your case since you have good PSU and Casing cooling. And the most important thing is do not trust the Abit Fixed Freq but mannuly set to 8:2:1.@285Mhz AGP=72 and PCI=36. Btw I disable the fast write so I do not know what will happen if I enable it. But one thing for sure, even before I disable of enable Fast write, I can not run the 3D testing @276+Mhz, but now I can.For 285Mhz*8, My machine is so far so good.
The SB cooling is nice in my machine, 3 blue lights when running, very steady and now the SB is very cool.
Wish you a good luck.
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