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Have you checked the motherboard codes or bios warning beeps?

Make sure the ram is seated properly (try using one stick at a time), and it might be worthwhile to remount your cooler if none of those work.

Well for one your motherboard may need a BIOS update. Since Z68 doesn't native support the Ivy bridge processors withou a BIOS update. Unless you recently purchased your motherboard then it might have a BIOS that supports Ivy Bridge. But to update just find a cheap Sandy bridge Pentium or i3 and update your BIOS then replace the pentium with your I7 3770K and you should be fine. If the power issues still occur then there could be other hardware issues. Please Make go back to everything thats supposed to be plugged in from the power supply to the components. Unplug everything and re-plug everything. Check for loose connections.

Hi, The CPU requires a BIOS update. You'll need a supported CPU for that.
http://www.gigabyte.com/support-downloads/cpu-support-p...

ah didn't realise that i needed a bios update, thats probably the problem thanks for the help.