I've had windows in installed on my Macbook Retina ever since I first got it just for running games. I was getting decent fps in Just Cause 2, Battlefield 3 and Skyrim running on high settings at 1920 x 1800 resolutions (30-50 fps) just a few days ago, I logged onto Battlefield 3 to find that I was getting less than 10. This has happened to all of these windows games. I have tried updating and downgrading the graphics card driver, windows 7 32 bit, windows 7 64 bit and windows 8 64 bit. After reinstalling Windows and re downloading all of the games, it apears it must be some kind of hardware issue. For battlefield 3 to be playable I now have to use the 480 x 720 resolution and low settings which is kind of pathetic. I think that the mac os graphics performance hasn't changed. This is only playing Amnesia and tf2 though because the only other game that I own on mac osx (Portal 2) has some bug where it wont open. Is it possible that windows is only using the intel 400 series graphics chip for some reason? This is the only thing that I can think of even thouhg it seems highly unlickly as windows does not support mac's graphics switching and doesn't even have the driver installed. Does anyone have any idea what the problem might be?
The problem is with the last EFI upgrade. There are numerous reports about this bug across the internet. Don't know whether apple knows about it though. Need to contact them.
Reset your SMC, it restores FPS and overall performance, but problems returns after some time. I personally have done it already two times.