My system:
Windows 7
2nd Gen Intel i7-2600 (3.4ghz)
XFX HD 6870
8 GB RAM

Issue:
I can get them both to run perfectly, with the graphic settings I want, as LONG as I enter windowed mode (or start in windowed mode) and switch to full screen. I almost get a solid 60fps in Crysis One this way with all settings on High except Textures (very high) and shadows (medium), in 1080p. If I just start the game up and go - when I'm zooming in far in the distance, I drop down to a solid 30fps. Doing the windowed/fullscreen thing fixes this every time, I don't think any graphics options are being disabled.

It's the same thing with Crysis 2, only I didn't notice at first because I'm using an HDMI cable, and I have to start the game in Windowed mode anyway and switch it to full screen to lose the brackets around my screen. I'm running Crysis 2 on all high settings, 1080p with DX11 and hi-res texture pack, get a solid 60 frames no matter where I'm at, I can't get the FPS to budge.

It's not a HUGE OMG help me issue, but it's still REALLY odd, and makes me wonder if I'll have to do this for Skyrim and Battlefield 3, if anyone has ANY input please help me out, this is really baffling.

Thanks for reading!