Question / Help Recording stuttering

[btreyd]

Hi, so recently I've been trying to record in 1080p 60fps, my computer runs fine and the games do as well. But the playback is very laggy and stutters (720p 60fps works fine). I understand that it probably has nothing to do with OBS its self, but I'm hoping someone can explain exactly what it is about my computer that can't run 1080p 60fps smoothly. Thanks.

Log: http://pastebin.com/dRhaHQv0