Powers Down After A Few Seconds

[Bellular]

Hello. My computer was pre build from Arbico. Since purchasing I have installed a 2TB Seagate HDD, 12gb Kingston HyperX RAM and a GTX560ti. Rather randomly It stopped booting. When I press power the lights on the motherboard flash green/red as normal but the system then shuts off. I thought it could have been due to the power supply, but after using a new Corsair 750W 80+ gold the same issue occurs. I have a motherboard speaker however it no longer works - when It did the beeps indicated no problems. Here are the specs:

CPU: I7 920
GPU:GTX560ti
MOBO:Gigabyte GA-EX58-UD3R
PSU:Corsair 750W 80+ gold
RAM: 3x4GB Kingston HyperX 1600mhz
HDD@ 2 TB Seagate

What I have done:
Fully cleaned the case
Tested each stick of RAM
Tested the GPU
Used a new PSU
Reseated the CPU heatsink (stock)

I think I will probably wind up having to buy a new CPU (probably a 3570k) and motherboard.

Any help would be fantastic!

 

[unoriginal1]

Heres a good list to go through. Do each step don't just read . It will help narrow down what is causing the issue.

http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems

 

[Bellular]

Heres a good list to go through. Do each step don't just read . It will help narrow down what is causing the issue.

http://www.tomshardware.com/forum/261145-31-perform-steps-posting-post-boot-video-problems

Hi. Thanks for the suggestion. Already worked through that list (very good list though), on both PSU's. Its setup on a testbench (aka mobo case) so there isnt any chance of metal shorting it. Still the same - mobo lights turn on, fans start then it dies.

 

[unoriginal1]

Instead of typing it out . Im providing another link.
Check out the *best answer* really good guide pertaining to the same issue.

http://www.tomshardware.com/forum/302360-31-computer-turns-split-shuts

 

[Smartd]

How old is your system build?

Do you have stock cpu cooler installed?

had an issue similar to yours where my system would boot up for like 3 seconds the everything shuts off. In the end my cpu was bad, some how it got burned out and also I had bad rams however the bad rams would still allow the system to randomly boot but would shut off on it's own.

try to independently test your cpu in a known working motherboard, if you don't have one take it to a shop and have someone try it for you.

 

[Bellular]

Instead of typing it out . Im providing another link.
Check out the *best answer* really good guide pertaining to the same issue.

http://www.tomshardware.com/forum/302360-31-computer-turns-split-shuts

Thanks . Ive got to head out for a bit but Ill get to work on that when I get back. I really need to get to the bottom of the mobo speaker no longer working.

 

[Bellular]

How old is your system build?

Do you have stock cpu cooler installed?

had an issue similar to yours where my system would boot up for like 3 seconds the everything shuts off. In the end my cpu was bad, some how it got burned out and also I had bad rams however the bad rams would still allow the system to randomly boot but would shut off on it's own.

try to independently test your cpu in a known working motherboard, if you don't have one take it to a shop and have someone try it for you.

Originally 3 years old - roughly when then 1st generation I7s were released. Since then ive upgraded components so all thats left of the original build are the cpu and mobo. I ran it with just 1 stick of RAM (slot furthest from the CPU) and the CPU. Everything powered up and died a second later.

 

[Bellular]

Ok I have breadboarded and unfortunatly still the same issue. There are no beeps from the mobo speaker - however I suspect the speaker is faulty. Ill buy a new one and try again.

 

[unoriginal1]

Ok I have breadboarded and unfortunatly still the same issue. There are no beeps from the mobo speaker - however I suspect the speaker is faulty. Ill buy a new one and try again.

If you got another machine laying around pull the speaker from it. (also a good way to test the psu)
Now it's time to check what is bad . Keep going through his steps for checking the psu first, etc.