Computer Cycling Power ever 15seconds on, 5seconds off (No Display)

[Trent12]

I don't know if I have ruined my motherboard or not...

I'll list out the steps and process I went through when building my new computer::
1) Place motherboard into case
2) Installed CPU onto motherboard (removed the plastic case on the motherboard)
3) Installed Ram
4) Screwed in the motherboard
5) Installed GPU
6) Plugged in most everything.

Here we go: I did not installed Standoffs. Nor did I plug in the CPU ATX12v cable -- only the MB cable (24pin).

I turned on computer, I think the Tower fan + CPU fan did 1 rotation before nothing.

I noticed the CPU cable, plugged that in. Tried turning on and was getting 1 rotation before dying -- had to unplugged PSU and back in before I could replicate that.

PSU was bad (bestbuy said it had a delay of 900 or something), bought new one from them.

New PSU, reconnected everything and now I get power -- fans spin, video card lights up and spins, CPU fan spins -- however, it only lasts for about 15 seconds before recycling automatically. It will power off, then power itself back on again.

Have I fried my motherboard? It is an ASRock H97 Anniversary...
I can't get HDMI to the monitor, period. No video output from either the HDMI port on the motherboard or from the Video Card.

This has been a 3 day ordeal now... I'd hate to have to buy a new motherboard but its beginning to look like I am going to have to, as I can't figure out what else it could be.

 

[RememberThe5th]

Try breadboarding (powering motherboard+cpu without pc case) case is maybe shorting out something.

 

[Dark Lord of Tech]

Best buy doesn't sell good power supplies.

 

[Trent12]

Original PSU is an EVGA 650W Gold Super Nova.

Replacement / test is ThermalTake TR2 600w

Both had same reactions when powered on -- computer would power, no video, computer would reset 10/15seconds later.

 

[Dark Lord of Tech]

Replacement / test is ThermalTake TR2 600w is worst than the EVGA , That TR2 is very very poor quality.