Is my PSU dead?

[NGTO1]

So this morning, I was on my computer and it was working. I shut it down. Then I turned the computer off and unplugged the PSU and everything else because I needed to open my case and check something. I unplugged a SATA cable from my HDD and plugged it back in.

I plugged everything back into my PC, turned the PSU switch to on, then turned my PC on and it refuses to work now. It'll either turn on and just sit there but nothing will show up on my screen. Or, it'll turn on and off repeatedly. It will only turn on for a second or two, fans spinning and LED lights turning on, but then it shuts off. Then it starts back up, then shuts off.

I unplugged everything from the mobo except the CPU and RAM, then I reset the CMOS. I then plugged the power back into the PSU and turned the PC on running the video cable right off the motherboard. Still no screen.

Quick build details:
Corsair TX850w semi modular
Intel i7-4770k
MSI G45 mobo
Dual MSI Twin Frozr 780s
16GB (8x2) Crucial Ballistix Sport RAM
DVD Drive
Samsung Evo 250GB SSD
1TB Caviar Black HDD

Do I have a dead PSU? It is 14 months old.

 

[Dark Lord of Tech]

Make and model of PSU?

 

[brispuss]

Make sure the motherboard 24 pin connector and the auxiliary CPU ATX_12V 6/8 pin connector are inserted properly.

Make sure the DIMM"s are seated firmly.

Bypass the case power switch by removing the case power switch connector from the motherboard. Try to boot the computer by shorting the two exposed case power switch boot pins on the motherboard using a screwdriver blade or similar metal object. Be careful not to touch any other pins.

If computer boots up and runs then the case power switch is probably faulty. If computer does not boot then try the following.

Try using only ONE DIMM at a time and in different slots as well if necessary.

If there are still boot issues, try other DIMM's (at hand or borrowed). If computer boots and runs then the original DIMM"s are faulty.

If the issues continue, try another PSU (at hand or borrowed). If computer boots and runs then the original PSU is faulty.

If issues continue then the motherboard is most likely faulty.

 

[NGTO1]

Make and model of PSU?

Oops, picked this as best solution by accident. :/

Corsair TX850 semi modular

 

[NGTO1]

Make sure the motherboard 24 pin connector and the auxiliary CPU ATX_12V 6/8 pin connector are inserted properly.

Make sure the DIMM"s are seated firmly.

Bypass the case power switch by removing the case power switch connector from the motherboard. Try to boot the computer by shorting the two exposed case power switch boot pins on the motherboard using a screwdriver blade or similar metal object. Be careful not to touch any other pins.

If computer boots up and runs then the case power switch is probably faulty. If computer does not boot then try the following.

Try using only ONE DIMM at a time and in different slots as well if necessary.

If there are still boot issues, try other DIMM's (at hand or borrowed). If computer boots and runs then the original DIMM"s are faulty.

If the issues continue, try another PSU (at hand or borrowed). If computer boots and runs then the original PSU is faulty.

If issues continue then the motherboard is most likely faulty.

Thanks for the tips. I ended up RMAing it to corsair who replaced it free-of-charge with a lesser CS850 because they no longer had the TX850 and wouldn't "upgrade" me. It's ok, I'm using it for a little while with two 780tis in SLI - carefully - because that's pushing the 850watt PSU to its limit. Intending on upgrading to 1000w, or even 1200.

Thanks again for the tips.

 

[Alectfenrir]

Make and model of PSU?

Oops, picked this as best solution by accident. :/

Corsair TX850 semi modular

I unselected the best solution as it was selected accidentally.

On Topic: Have you tried paper clip method to test if your PSU is still alive?