X800XT overclocking problems

[Jupiler]

OK, here's the deal :

I bought an X800XT (PCI-E) last week, bulk version, ATI sticker on cooler.
I put my WB on it and installed the latest drivers, along with ATI Tool.
I wanted to see how high the GPU on the card would go with ATI Tool.

All goes well until the GPU reaches around 550Mhz.
At that speed (sometimes at 548-549Mhz), my system freezes and reboots after a few seconds.
I checked if the block was seated well, which is the case.

Tried again, but same thing happened. System freezes once the GPU reaches the 550Mhz mark.
I uninstalled the drivers and ATI Tool, tried the 5.6 and 5.7 drivers, along with ATI Tray tools.
Same thing happens. Even with ATI Tray tools, my rig completely freezes around 550Mhz GPU.
The GPU temps look OK : 34-35° idle and 43-44° load.

I thought that with both ATI Tool and ATI Tray Tools, once the GPU goes to high and it finds artifacts, it backs down in speed and checks how high it can go.

Anyone knows what might causing this?
Any help is greatly appreciated.

System specs :
DFI SLI-D (623 bios)
3000+ Venice
2*512 MB OCZ PC3200 rev.2
ATI X800XT (watercooled)
520 OCZ Powerstream
....

[CaTalyst.X]

my x800xt did that w/ those self overclocking programs too, at a certain mhz it would just freeze no matter what I did, just do it manually and youll be fine, my card went 40+mhz past where atitool would crash

-CaT

[Jupiler]

Thx.
Will give it a try.
Just did a fresh install on another partition, and now it crashed at 510Mhz GPU. Totally weird. :stick:

[Moonman]

Just try the old way. 3Dmark, rthdrbl.
Mine also crashed at certain (low) speed when searching for max clock with ati tool.

[iboomalot]

those cards top out around the 550 core range you need to volt mod to reach higher clocks

[Highland3r]

Might just be a poorer clocking card perhaps?
The fact that it freezes then reboots might suggest otherwise however... You got VPU recover enabled at all?

Have found (in 01 anyways and its probably the same elsewhere) that theis card tends to lock rather than badly artifacting....