Computer starts up 10 seconds, shuts down, restarts on its own and works

So I bought some new upgrade stuff for my PC. Here is the new hardware.

1 of Intel Core i7-2600K Processor 3.4GHz 8 MB Cache Socket LGA1155

1 of Corsair Vengeance Blu 8 GB (2X4GB) PC3-12800 1600mHz DDR3 240-Pin SDRAM Dual Channel Memory Kit for Intel and AMD Platforms CMZ8GX3M2A1600C9B

1 of Corsair Hydro Series H80 High Performance Liquid CPU Cooler (CWCH80)

1 of ASUS LGA 1155 SATA 6Gbps USB 3.0 Supported Intel Z68 ATX DDR3 2400 Motherboards P8Z68-V PRO
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The old stuff:
Xion AXP-1000R14HE Lan-Party Edition 1000 Watt SLI Certified Cross Fire Ready 80 Plus Bronze Certified PSU

EVGA GeForce GTS450 SuperClocked 1 GB GDDR5 PCI-Express 2.0 Graphics Card 01G-P3-1452-TR

2 x Seagate Barracuda 7200 1.5 TB 7200RPM SATA 3Gb/s 32MB Cache 3.5 Inch Internal Hard Drive ST

Western Digital 500 GB Sata 6.0 Gb-s 16 MB Cache 3.5-Inch Internal Bare-oem Drives31500341AS-Bare Drive
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Now that we got that out of the way, This isn't my first computer I built. I think this is incredibly weird that the computer boots up by pressing the power button on the motherboard without any problems, but when I press the power button on the computer case it boots, but after 15-20seconds without any activity on my monitors it shuts down, then 3 seconds later, reboots on its own with no problem at all. I also tried some solutions. My first one, I didn't have all those brass spacers on my MB I only had 6, now I put all 9 in and tried to start it up, same thing happens. Then I tried adding in one thing at a time, I tried my Motherboard with my power supply unit, same thing still occurs. I really doubt it my PSU just to the fact that after it restarts it works without any difficulty for as long as I want. I'm curious as to why it's doing this. Hopefully someone can help me out. Thanks.
 
Memory

So I noticed I forgot to pull my RAM memory out when testing, I did that now, The motherboard and PSU just stay on while on the motherboard the light for RAM stays lit for as long as I want my PC to stay on. When I put one stick in it goes past that light to check my video card then run the bios. but shuts down either on video card or sometimes bios. I have 2 sticks on RAM and they both react the same way. I wonder if it's a faulty motherboard with a bad bios.
 
Sounds like you have the computer overclocked using the wrong settings. Set the bios for it's defaults and see if the computer boots correctly
 
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