I've done quite a bit of research about this problem as I constantly get it and I'm unable to play my favorite game in my favorite series for more than 10 minutes without getting this error. Many people in different forums (especially the Crytek forums) are getting this error. It seems to be a common thing with higher-end graphics cards and newly released games that are graphically very taxing.

Look at this link and read Sultaan's posts/fixes: http://www.mycrysis.com/forums/viewtopic.php?f=65&t=59764&sid=de8e77265e4f2149f5a6633857bf3124&start=20

There are 2 primary solutions many people have come up with to fix this issue. The most popular one is to slower raise your graphic card voltage levels by very small increments until the error stops. These increments should be very tiny (0.10V - 0.15V per increment, and don't go over 0.40V max) . Refer to the link I gave to see the increment range, DO NOT DO THIS RECKLESSLY, make SURE you know how much you're incrementing it by and what is safe for your card.

The other is to lower any Memory Overclocking to it's default setting in your bios.

I will be trying both of these today to see if they work for me, but it worked for a friend of mine.