Borderlands 2 Jittery, lag spikes, stuttering not really sure.

SPECS:

Motherboard: M4A88T-M
Processor: AMD Phenom II X4 965 Black Edition 3.4ghz
GPU: Powercolor HD Radeon 6850
Hard Drive: Seagate 500GB
PSU: Coolermaster eXtreme Power 500W
Ram: 8gb xjaws 1333mhz ram)
OS: Win 8 64 Bit

I get around 60 - 80 fps in Borderlands 2 but for some reason the game doesn't play smooth occasionally it will stutter or lag for like 0.1 seconds (not really sure) may not seem like much but it is really annoying and kinda ruins the game a bit.

Any help would be appreciated.

This is a file from AMD System Monitor showing my CPU,GPU and Ram usage its needs a program like OpenOffice or Excel to open

http://www.mediafire.com/myfiles.php#myfiles

Thanks