When I record at 60 fps at 1080p using Intel Quick sync sometimes when the frames in game drop to 30 or 40 it can cause the video to shudder and screw up totally.
Then when I drop the recording fps in Action to 30 fps 1080p it drops my frame rate in game down to 30 fps like it is locking the frame rate. So I can record fine at 30 fps its just it stops my game from running at vsync 60.
I am not sure why the recording settings are effecting game fps.
Games like battlefield 3 seem to record at 60fps fine as long as I set the action process under task manager to real time instead of normal. Otherwise it seems to screw the video up and shudder in the recording.
League of legends does not seem to work well at all. I might get 2 mins of good video via that before it falls over and stops recording.
System specs: i5 running @ 3.7ghz Ivy bridge, 8gb ram, NVidia 670 Windforce 3.