CPU stable? Check! Ram stable? Check! GFX? CHECK! 3Dmark05... no!

[Noxis]

Ok my system is stable setup with 9x288 and 333 on the ram. With a touch over 1.6v to the CPU. Very cool at 2x prime load with around 43 - 45c (room temp dependant). I have had it prime for 10 hours plus at these speeds and memtest did over 25 passes of test 5.

The gfx is a AGP XFX 6800 Ultra bios flashed to Ultra Extreme and water cooled. Its 100% stable as I have been using it for the last year in my FX51 setup.

However running 3DMark05 it fails when attempting to do the CPU tests. Also HL2 crashes at the menu screen.

I have tried max NB SB HTT and AGP volts which I *think* helped a little but I wasnt convinced as it could have been one of those random overclocking moments where it just lasted a little longer before crashing. However if it did help this would indicate that the HTT while stable dealing with priming and memtests cant handle the increased bandwidth from gaming at 288 speeds.

Due to the poorer mem controller on the X2's I cant run higher than about 240mhz 1T so I have a bit of a pants clock at the moment of 2.520ghz CPU with a 333 div on the ram.

My Spec is in my sig and I was hoping someone will have a magical remedy.

[TMM]

The Abit AV8 is not usually 3d stable over 255-260HTT.

When i had one, the only way to get it 3D stable over 255HTT was to (IIRC, these might be wrong):

set LDT to 2x, HTT:AGP:PCI (AGP lock/speed) to 8:2:1

or

set LDT to 2x, HTT:AGP:PCI (AGP lock/speed) to "74 Fixed".

Hence the Av8 sucks and i got rid of mine for a Neo2 - sorted out all my problems that i had with the Av8.

[Noxis]

The Abit AV8 is not usually 3d stable over 255-260HTT.

When i had one, the only way to get it 3D stable over 255HTT was to (IIRC, these might be wrong):

set LDT to 2x, HTT:AGP:PCI to 8:2:1

or

set LDT to 2x, HTT:AGP:PCI to "74 Fixed".

Hence the Av8 sucks and i got rid of mine for a Neo2 - sorted out all my problems that i had with the Av8.

I do have the newer revision and it can crunch numbers stable at 300mhz. Plus if there was a problem with the AGP/PCI locks as you are suggesting i'd get HDD corruption?

[TMM]

so could mine - i was Prime95 stable at 310HTT, but couldn't even run through 3dmark03 at 260.

it not a direct problem with the locks, just a problem with the chipset itself (iirc Abit said it was a hardware problem with the K8t800 and if anything they would need a revision to the board as a bios update couldn't fix it). But changing the lock to 74mhz seemed to fix the problem for people who had cards that could handle it.

At the time i had a 9800Pro that couldn't handle 74mhz AGP. oh i remember what i had to do now - LDT @ 2x, ram to "DDR266", AGP lock thing to 8:2:1. then i was 3d stable up to about 290HTT, but it was absolutely pointless as my ram was going to slow.

[targ]

i had the same, i had a rev 1, so it had a very low max HTT (285) but it would not 3D bench over 260. 258 if u want to be safe.

sorry mate, hardware problem, nothing you can do.

targ