sudden framerate drop

[J_man86]

I'm having framerate problems. My system is great and runs Crysis at full settings. I played Arkham Asylum for hours on max settings without it messing up and then all of the sudden my framerate dropped to like 7. I restarted that game and the computer several times. I updated my gpu drivers, downgraded the drivers, and updated them again. And it still runs horribly even at the lowest settings. please help! It happens the worst when characters or large rooms are on screen. I know that sounds like inferior hardware, but trust me it's not. Built the PC myself, I know what I'm doing.

(I'm a noob poster so sorry if i did something I wasn't suppose to.)

Fixed it. somehow PhysX got turned on. It wouldn't even let me turn it on before cuz i have a radeon card instead of nvidia. then somehow it turned itself on. idk. hope this helps other people.