9800se: Damaged pipeline?

Softmodded a 9800se to unlock the extra 4 pipelines. 3dmark03 runs fine, and I went from a score of 3426 to 4111. However, I get a strange yellow checkerboard effect when I run atitool to find max core and mem. I am assuming that I have a damaged pipeline, but I am a little confused because 3dmark03 seems to run without any problems. Is this correct, or is there another reason I would see this funky checkerboard only in atitool?

BTW - It only happens when I try to find max core and mem. Otherwise the 3d view looks completely normal.

It could be overheating, but likely you DO have a damaged pipeline. The damage may not always show up though, and certain games may run flawlessly, while others will be terribly distorted.

I think you're right. I have a vf700cu on it, and I sinked up all the ram so I don't think it is overheating. I am going to drop it back to four pipes and see if the problem persists.
Thank you,
cj