I recently built a new system for Christmas; CPU: i5-3470 GPU: XFX 7870 core edition RAM: 8gb supposedly 2133mhz, but I can only have 1833mhz, I've always felt this graphics card had low performance since I've got it, I'm getting below 15 fps maxed out at 1080p on games such as hitmam absolution, the witcher 2, and Far Cry 3. My friend had recently got a pre-built computer, of which he has the same CPU, 4gb of RAM, and a 7770, yet in games like Minecraft, with the shaders, he gets 10 more fps, but I should be getting much more than he is. Is there anything that could be limiting my card? maybe through installation problems? Also, my system is rather un-responsive at the very start of, well, start-up, but I have no idea what that means.. I should probably add, I did get a little, and I mean a really little amount of thermal paste on the CPU, but it works fine so I assumed there was no fault. please ask of any details that may be important.
Check your CPU temperature make sure it is not running hot above spec (I think 67 celcius is the max temp for that CPU before it starts throttling). Ensure that you are not using more than 2xMSAA for your games. Make sure that for Witcher 2, you have Ubersampling turned off.