Mike,
I found a workaround to my problem. It should work for you as well. It's a bit of a hack, but it works.
Here's what I did:
download AOCLBF:
http://forum.bitcoin.org/index.php?topic=10264.0keep a downloaded copy around somewhere.
Install it as instructed (basically place the 3 files into your guiminer filder location).
You DON'T have to use this miner for mining, but it will allow you to OC and set fans
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
The very first time you run it, it will ask you how many miners to create. I specify the number of GPUs, not the cards, so for the 2 6990 + 6850, I tell it to create 5.
You will see "client tabs" (ignore these for the moment) and a tab for each GPU. Here I use the GPU-related tabs to set my clocks and fans. I answer "no" to setting on next startup.
After I OC the way I want, I simply start my usual miners. I do not use the AOCLBF for mining (at least not yet).
Here comes the tricky part. On next restart/reset, this program most likely will not detect your GPUs correctly. This is probably why MSI Afterburner, trixc and others don't work either.
What I do at this point is delete all the files related to AOCLBF (this includes a clocks.xxx file) and reboot.
After reboot I repeat the install process and keep going.
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
I hope this solves your issue Mike.
If this helps, feel free to send me that bounty, but I won't cry if you don't: 15KwcqgcxjsXx6XGJgv56Ps6AjbeQP3Ge5