STRANGE problems clocking A64 on Shuttle AN50R with Radeon 9800XT!

[Radical_53]

I do have some really weird problems here, maybe someone knows them, and might help me with it.

Right now, my CPU does 2.45GHz on water, with 1.7V. Prime stable for more than 2 hours, stable with Seti@Home all night long.
Now, I can run AquaMark3, 3DMark2k1, 3DMark2k3 without any problems, as long as I don't touch the frequencies of my Radeon XT.

Aquamark runs when I clock it, but 3D2k1 gives me a blank screen after CarLow, no matter how often I run the first test (like 15 loops CarLow, no problems).

My settings are like this:

Shuttle Bios 25
Booting with:

CPU HT 200MHz, RAM 166MHz, timings 2-3-3-6
AGP 67MHz (for the PCI lock)
AGP 3.0 set to Auto
FW disabled (didn't give me any speed boost)
LDT 2.5

CPU Vcore 1.7V
RAM Vdimm 2.8V
LDT 1.5V

Before setting LDT voltage a bit higher, the machine wouldn't even run the benchmarks with the CPU clocked to 2.45GHz, even when Prime or Seti didn't report any problems.

Still, I can't run them with my graphics card clocked higher. The 9800XT runs well while the CPU runs @default.

My UPS reports ~50% usage while running 3DMark without the clocked XT, so power shouldn't be the problem.
Also, mit power supply has rock stable voltages, as I've never seen before (better than my Antec 550W).
MBM5 reports 3.31V, 5.02V and 11.67V.

Maybe someone can help me out... I'm really out of clues. I do use the Omega 4.2 driver, now with VPU recover disabled (had it enabled before, didn't change anything).

[RootX]

If you change the multi with clockgen, then you should consider lowering the LDT to 2.

If you're running @ 10x245, then I suggest u try removing 1 stick of your 512MB mem.
Many ppl(including me) had problems running 2x512 MB mem. I have the shuttle too, with 2x512 OCZ 4000 gold. Running the sticks at slots 1&2, simply didn't work out... the system could n't load windows at all. Tried 1&3, everything went fine but no 3d benchies.
So I had to remove 1 stick to stabilise my system.

Of course, this is not the rule but u could give it a try and let us know how it went.

[Radical_53]

Well, I'll try one stick... still, I know many people running 1Gb without problems after some "testing".

I just did a benchmark run with my CPU @ 267x9, which resulted in 24.2k in 3D2k1.

Stupid thing is, that changing multipliers is mostly a thing of luck right now. Sometimes works, mostly not :(

[Radical_53]

Tried with one stick now... same thing. A friend of mine told me that the problem would be because of my CL2 sticks...

Yet, I do have one even bigger problem. My Radeon died today, so I'll have to wait for a replacement card... :(