Does this only happen in Demigod?

Geometric Instancing in CCC, plz toggle it.

Only in Demigod and what is geometric instancing? Couldn't find that setting in there.

couldn't find it? 

well, seeing as i don't have an ATI card myself i can't help you directly. anyways, the reason i said it was because that looks like a very similar issue SupCom has.

Any help is greatly appreciated.

Have you updated drivers lately? Heat is another possible cause.

can anyone point KingAssmar in the direction of Geometric Instancing? it's best to get that one under the bridge ASAP before we run off hunting for thermal and power issues.

MY GOD - HE HAS IT!

I too have this problem! I searched in vain for information about it around here as well. Sorry I sound so excited, but I'm just glad that im not the only one with problems with my 4870!

I too also have the problem on Dead Space.

This issue is an absolute gamebreaker. I've searched in CCC for Geometric Instancing (as well as fiddled with tons of functions in order to try something that works).

I've tried different drivers, so I'm pretty sure it's not driver related, and the card heats up to an acceptable temperature.

http://forums.gaspowered.com/viewtopic.php?t=33888

try the above link, as it turns out CCC doesn't have it but ATI Tools does!

Now, what does geometric instancing do? Should I keep it enabled for other games?

it shouldn't hurt. that said; wikipedia has a great explaination of what happens.