Sapphire 9600 XT - not tunable ?

[slingshot]

Hi,

I have a Sapphire Radeon 9600 XT (Fireblade version with 325 (650DDR) Mhz Memory-Speed) and using a VGA Silencer 3 GPU Cooler (which works great).

Before I had that 9600XT, I had a 9600 Pro which I could easily overclock, but the new 9600XT is directly bringing up Artifact Issue when I just try to start the GPU tuning.

When playing, I don't have any Artifacts at all, but it kinda confuses me that AtiTool can't overclock even 0,50 mhz more than the default 500 Mhz.

Any Idea?

Slingshot
PS: The 9600 Overclock lock Override Switch is tuned on, so that it "should" work.