Guess I should have included a little more info in my first post..
Here's my setup:
Intel i5-2500K @ 4.2GHz
2x ASUS DirectCU II 2GB Radeon HD 6950
16GB DDR3 Mushkin Silverline RAM
Asrock P67 Extreme 4 Mobo
1TB Samsung F1 Spinpoint HDD
HAF 922 Case
ASUS Optical Drive
CORSAIR Enthusiast Series TX850
Windows 7 Home Premium x64
3x Dell 19" Monitors
I use this computer for about 90% gaming and the rest is used for School/MS Office/browsing etc.... I had been using the same computer (Dell Dimension 5150 Desktop) for the last 6 years and decided that it was time to do myself a favor and build me a computer worth having. To be completely honest I saw an Eyefinity setup for the first time was instantly in love with it
Not to mention the newest addition to my favorite series (BF3) being right around the corner
The reason I don't use Afterburner for my main program is because I can't change the voltage with it. I've tried changing the config. files for it to unlock voltage controls but I cannot get it to work. I've been told/have read that since my cards are non-reference versions (ASUS) the only program I'm able to use for voltage tweaking is Smart Doctor. So far I've had no problems controlling my fan speed with CCC. I have both cards running at 65% fan speed during gaming, which for 2 cards is alot quieter than I expected thanks to the DirectCU II cooling. If I could successfully control voltage, fan speed, and OC with just Afterburner alone, trust me I would.
My temperatures don't stay at 75'C all the time, only when gaming, and that's only my top card running in CF, the bottom one doesn't even reach 60'C. At Idle my top card chills between 54-57'C, and the bottom one at 37'C. Since these are 3 slot cards they're right next to each other on the Mobo. My room is also not air conditioned right now so it's a little on the warm side. I'm sure the temps will be cooler come winter time. At MAX I've seen my top card reach 85"C... But even that's not extreme is it?
Finally as to why I would like to overclock my Crossfired 6950's for everyday use..... My monitors in Eyefinity push my resolution to 4080x1024. I know that isn't super huge or anything but it's a whole lot bigger than one of my 1280x1024 monitors by themselves. As of right now I can play BC2 with very very smooth frame rates at my resolution. I haven't used FRAPS in a while so I don't have an FPS number to give, I'll post back with one when I get the chance. Bottom line is I wanna safely push my 6950's as far as they'll go... We all want a little more graphics HP right? And as far as my CPU goes, I would hope an i5-2500K @ 4.2Ghz would be fast enough to keep up..
Thanks for the input so far guys.
EDIT: While running FRAPS in BC2, I am averaging almost 90 FPS throughout the whole game, while indoors my FPS is spiking into the 130's, while the lowest FPS i happened to notice was in the high 70's. I'm quite happy with that, I didn't think it was going that high