I have a Sapphire Radeon HD 6950, only GPU in my computer. When I enable my second monitor my framerate sits at 60 in games/windows/whatever (everywhere) then drops to ~25-30, then back to 60. It does each for about 10 seconds and goes back and forth. What I have running doesn't affect the frequency or severity of the framerate drop. This occurs on both displays.
I had attributed it to 2 displays being extra strain on the graphics card because I only noticed it in games, but today I've been watching it and it's happening always. Turning off the second display puts me at a flawless 60 fps with no dips.
Is this common, or does anyone have any idea what the issue would be?
Full specs if needed:
CPU: Intel Core i5-3570K
CPU Cooler: Cooler Master Hyper 212 Plus
Motherboard: Gigabyte GA-Z77X-UD3H
Memory: Corsair Vengeance 8GB (2 x 4GB)
Video Card: Sapphire Radeon HD 6950 2GB
Power Supply: Corsair 750W ATX12V / EPS12V
OS: Windows 7 Ultimate 64 bit
This happened to me on my 6850 on a single monitor. What I did is re install the drivers. Delete the old ones and install the new ones. Now I have two screens as they run fine. I also re installed windows but I'm sure you don't need to do that.