How do I tell which components survived after a power supply failure?

A couple days ago I booted up Left 4 Dead, but then heard a pop and my computer turned off. It smelled like dead electronics so I unplugged the computer. I figured it was a power supply failure, so I ordered a new Corsair HX520 and tried to install it today, hoping that was the only thing that needed replacing.

However my computer most emphatically did not work. Case fans turned on, a few motherboard lights and optical drive power lights turned on, but neither my GPU fan or my CPU fan turned on. Also one of my hard drives sprayed a few sparks from its underside and a bit of smoke came from it. I figure that one is dead. There was also no signal to the monitor or beep codes. I quickly turned the computer off to avoid any potential CPU overheating and tried with only 1 stick of RAM and no hard drives and got the same result.

What does this mean? Does the GPU fan not turning on mean the video card is shot? What does the CPU fan not turning on mean? Is the motherboard dead as well, or the CPU, or both? Should I just spring for a new computer at this point?

(edit) Also, can a power supply failure hurt your RAM?

RandomEngy

Posted 2009-08-20T00:42:59.837

Reputation: 432

Sigh... I'm living through the first half of this story. Replacement Psu arrives tomorrow. – Basic – 2015-01-05T09:37:34.603

Are you 100% sure that both the CPU fan and GPU have power? In other words that you've connected the CPU fan to the MB and connected your GPU to your PSU if it requires it. – lyarwood – 2009-08-20T00:49:14.373

Yes, I've hooked up the power to them. For the GPU I swapped cables and made sure the connection was firm, and for the CPU I tried both the 4-pin and 8-pin CPU power connectors. – RandomEngy – 2009-08-20T00:57:06.460

I live in a country where power failures happen regularly. The interesting thing is my Asus laptop, without the battery (died a year ago) works perfectly even after a power failure... I wonder if there are any desktop components equally resilient. – None – 2013-01-06T11:12:38.080

Answers

Final outcome: PSU, system drive, motherboard, CPU and GPU were all dead. The memory survived, and a tech at Fry's repair department said that if you don't see burn marks on memory, it probably is fine and can withstand power surges.

Also if you try a fried CPU in a perfectly good motherboard, it can kill the motherboard. Bottom line is if your motherboard is fried, you better replace the CPU as well. Just trying to diagnose it can burn more perfectly good equipment.

RandomEngy

Posted 2009-08-20T00:42:59.837

Reputation: 432

Could you accept this as the answer to the question. This attracts people's attention to the correct answer as soon as they view the question and 'closes' the question. Thanks and I'm glad you found a way out of your mess :) – n0pe – 2011-04-17T22:15:49.023

The fans dying does not necessarily mean that the CPU and GPU are dead. It looks like either the CPU or Motherboard is fried, but unfortunately unless you can see visible damage (burnt wires, blown capacitors, etc.) you are pretty much going to have to test each component individually. Have a buddy with a similar system?

Ryan

Posted 2009-08-20T00:42:59.837

Reputation: 1 728

I don't know anyone else with a Core i7, sadly. – RandomEngy – 2009-08-20T00:52:37.133

If you have another computer or a friend's, you could test the Video card on it.

But looks like your motherboard is dead though.

Decio Lira

Posted 2009-08-20T00:42:59.837

Reputation: 433

Video card is dead. I'm not certain about the motherboard yet but it seems quite likely. – RandomEngy – 2009-08-20T02:30:19.090

I have the same problem .Because of a power surge from the power supply my GIGABYTE motherboard fried with no sign of burn or capacitor leaking,but fortunately my CPU and RAM are working good.I bought a new power supply and ASUS motherboard and they work efficiently with the survived components.

Mahmoud Rekaby

Posted 2009-08-20T00:42:59.837

Reputation: 11

Sounds like your motherboard went. Are you sure the pop was from the power supply and not a cap on the motherboard?

Pyrolistical

Posted 2009-08-20T00:42:59.837

Reputation: 1 132

I doubt a motherboard failure could cause sparks and smoke to emanate from my hard drive. – RandomEngy – 2009-08-20T00:51:51.627

Though I am not entirely certain where the pop came from. The PSU smelled more strongly than the motherboard however. – RandomEngy – 2009-08-20T01:00:32.200