Computer boots up for about ten seconds, then shuts down.

[weidnath]

I have a new build that I just finished working on, but when I turn the system on, it boots up, displays a startup menu for about 10 seconds and then shuts down. When I restart, it remains on for a shorter period of time than before, and sometimes doesn't even make it to the menu. The startup menu that it displays asks me to enter a device to boot from, and says that if no device is selected within five seconds, the next device will be selected. I've looked in the user guide for my motherboard but it didn't seem to say anything about this menu. I'm wondering if this is caused by a power/cooling error or if I need to enter a device in the startup menu.
Here are the components I'm using:

AMD FX-8350
http://www.newegg.com/Product/Product.aspx?Item=N82E16819113284

Asus M5A97 R2.0
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131873

EVGA GTX 760 superclocked
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130932

Seidon 120V liquid cooling kit
http://www.newegg.com/Product/Product.aspx?Item=N82E16835103195

Corsair CX600M 600W Power supply
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139028

Ballistix 4GB DDR3 RAM
http://www.newegg.com/Product/Product.aspx?Item=N82E16820148543

Antec GX700 case
http://www.newegg.com/Product/Product.aspx?Item=1N8-001K-00002

WD10EZEX 1TB 7200 HDD
http://www.newegg.com/Product/Product.aspx?Item=N82E16822236339

 

[ssddx]

if it turns on for a few seconds then shuts down and progressively turns into a shorter time period that points towards a cooling issue.

check your cpu fan... is it spinning?

did you apply the thermal paste correctly and seat the cooler correctly? take it off and try again (replace with fresh thermal paste)

 

[weidnath]

The fan is spinning and there appears to be plenty of thermal paste. I felt it after letting it run until it shut down and it wasn't noticeably warm. I also checked the RAM, and the startup menu recognizes that there is 4GB DDR3 1333 (which the MoBo does support). I couldn't find any place where the MoBo could be shorting against the case either.

 

[ssddx]

did you try reseating the cooler and running with the case side off?

 

[weidnath]

Found the problem! It was indeed with the cooling system. I had neglected to plug in a power cable :/ No problems now, thanks!