OK so heres my problem I have just built a new PC and I am having problems.  I was having these problems on my old pc so I am a little confused.  Let me give my specs for a little clearity.  

CPU- Intel core i7-920
Mobo- ASUS Rampage Extreme II
MEM- Corsair Dominator DDR3 6GBs
VIDEO- XFX GTX280 in Dual SLI
POWER- Corsair 1000 Watt
OS- Vista Ultimate x64

So basically what has been hapening is about every 30 to 45 mins or so and then sometimes it may go an hour and a half before it happens. My computer freezes, I cant move my mouse, If audio is playing it starts skipping, if video is playing it skips and then the video starts playing again but runs slow to catch back up with the audio.  This can happen at any point not just when playing audio or video.  It is just noticable when playing audio or video.  Any help would be great, and if there is any more questions concerning this just ask.                                 
 

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