I got a brand new Radeon 6950 2GB (I upgrade for CoD) and Im having this problem, the game is not clocking the core and the memory at the stock full power Mhz, the values are those of the desktop.
You can check the values (and others like temp and GPU load) with GPU-Z.0.5.2, start the sensors, play 20 seconds and ALT+TAB to check them (they will go down to desktop level if working properly, but you can see the graphic chart). When using any other game (I tried 3 or 4 with this card) the chart show the throttle up in game and the throttle down when ALT Tabbing to desktop.
For now Im using MSIAfterburner overclocker utility that show current values and a nice graphical chart to Overclock the core and memory Mhz by 1 Mhz only, no risks that way. I put 801mhz as core and 1251mhz as memory clock and press apply button, then go into the game (im not using the option to remember the OC with every boot). When I ALT+TAB to check after playing Im seeing the correct throttling up to those values when in game in the chart.
So is a BUG!!!!! Some ATI cards show it and others dont, Im using Windows 7 32bit (still working on a 64bit install on other partition) with the 11.3 Catalyst driver.
I see the potential of the sim, but all the little bugs and cumbersome menues, controls setup for joystick, etc are driving me mad. We need a lot of sandpaper
