Hello, I've recently purchased an AMD Radeon HD 6990. Excited to test out this card, the first thing I did was try to play a few games on ultra settings. GTA4 with the iCEnhancer mod chokes and gets about 6fps, Dragon Age 2 has micro stutters, and Rage's textures load incredibly slow. Something seemed wrong to me, as I had better performance with my previous card, an HD 4890. So I decided to benchmark it. I tried to use 3dmark11, but it kept giving me an error saying it could not scan the system info, and there was a .dll error. Anyways, I finally found a benchmark tool that I could use; FurMark. So I did a few tests, and time and time again I got absolutely terrible scores, no matter what settings I used. Usually around 12fps. If I made the resolution as small as possible, and disable every extra option, I could manage to get almost 30fps. Clearly something is wrong, but I'm not sure what. I've updated my drivers to the latest available. Any suggestions would be a big help. Here's my rig:
Intel core i7 920 @ 2.66MHz
Asus P6T Mobo
12gb DDR3 1066 @1.5V
AMD Radeon HD 6990 (XFX)
Sharp HDMI LCD - Max Res. - 1920x1080
WD caviar black 750gb hdd
1000W Rosewill lightning PSU
Sorry if some of that information was unnecessary; just trying to be as detailed as possible.
EDIT: My apologies if I don't respond right away, I'm currently living in Japan, and it is late here.
It could easily be a software issue. I notice that your clock speeds in GPUz are dfferent from each other, that is a little strange. I would completely uninstall all graphics drivers, reboot and freshly install the new ones. There could be some old .dlls and bad leftover configurations from your old card.
Once you do that, make sure you go into the CCC and move the powertune slider all the way to the right. Try both of those things and see what happens.
That seems to have got it. 3dmark still won't work, but the results from the FurMark test were much better. Also, the gpu clock speeds evened out at 830MHz and the texture fillrate equalized too. I still haven't checked it with games yet. but I'm gonna try that now.