Having lots of problems with computer

Hello,
I am having a lot of problems with my homebuilt PC.
Specs:
Gigabyte Z68MA-D2H-B3 Motherboard
Intel i5-3570k Processor
OCZ ModXStream 600w PSU
Msi Nighthawk Case
Gigabyte Windforce GTX 550Ti
Kingston 2x4GB RAM.
Seagate 1TB HDD
Sony DVD Drive
Stock Cooler, Arctic Alumina Paste
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Problems:
So I have connected all of the power, I have installed the stand-offs. I then proceed to start the PC. I can hear all the components starting up including the GTX 550Ti. The only thing that is not starting up is the CPU Fan. I tried plugging the VGA Port on both the Intergrated Graphics and the GTX 550Ti but nothing shows up on the screen. When I started up the computer the fans stay on for about 10 seconds and then it restarts. At the beginning of each power cycle the CPU fan twitches.
I really don't know what to do with my system right now; please help?