PC Diagnosis (not powering on)

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Hi all,

We just had thunder + lightning, I was just shutting down the computer when there was a small pop noise. The computer didn't seem to shut down instantly, but it did go off after a few seconds.

I left it an hour until after the lightning had passed, when I tried to turn it back on the fans went full blast for 10-15 seconds and then it shut down. I tried once more to turn it on but now it doesn't turn on at all.

The mobo SB_PWR light is on/green but apart from that it seems unresponsive. It was plugged into a surge protector and has a Corsair TX 650W PSU... this is the second Corsair TX 650W PSU I've had, the other died about 6 months ago (but when that one died the pop was a lot louder, it smelt and everything shut off instantly).

Does anyone have any idea what I can try / what part(s) are likely to be dead?

Thanks in advance for any help!
 
Thanks for the reply, unfortunately I don't have access to another system to try it in. If it was the PSU wouldn't the mobo light be off?
 
Yeah,

PSU: Corsair TX 650W
Processor: Intel Q9550
Mobo: Asus P5Q Pro
Graphics: Asus 260GTX
RAM: Corsair TWIN2X4096-6400C5C 2x2GB DDR2
HDD: WD6400AAKS 640GB

...in a Antec P180 case.
 
Without having an additional PSU to test its gonna be pretty difficult to diagnose. So when you turn your computer on, nothing happens now? Have you tried manually switching off your computer at the back on the PSU then trying again? Can you smell any burning inside the PSU? If its not the PSU the lightening could have triggered a surge to one of your components and from the sounds of it, the motherboard, but I dont' want to jump to that conclusion just yet : )
 
Yeah, nothing happens at all now when I push the power button. I've tried switching it off/on at the back but it made no difference. There's no smell of burning anywhere.
 
Its definitely 1 of 2 things, its either the motherboard or the PSU. As I said without having additional components to test the problem with its gonna be difficult. Is the machine built or did you buy it pre-built?
 
Hi all,

... this is the second Corsair TX 650W PSU I've had, the other died about 6 months ago (but when that one died the pop was a lot louder, it smelt and everything shut off instantly).

Well, you now know the Corsair RMA procedure, tell them that the replacement they sent also went pop and send it back to Corsair for a new one.

Athough there is no guarantee that this time it did not take out the mobo or any other components as well.
 
Its definitely 1 of 2 things, its either the motherboard or the PSU. As I said without having additional components to test the problem with its gonna be difficult. Is the machine built or did you buy it pre-built?
I built it, apart from the PSU dieing 6 months ago it had been running fine, but as I'm sure you can tell I'm relatively clueless when it comes to computer hardware :p


Well, you now know the Corsair RMA procedure, tell them that the replacement they sent also went pop and send it back to Corsair for a new one.
Unfortunately I do... last time it took £25 and a 6-week wait to get a replacement so if it is the PSU I'll just buy a new one.
 
Unfortunately, only way we are gonna solve this problem is either ask to borrow or someones PSU or to go out and buy a new one and see if that fixes things, if not then you know its the motherboard.
 
Thanks for the reply, I don't know anyone that I could borrow one off so I'll probably just buy a new PSU on Monday which will allow me to check if it's the PSU or not. Even if it's not I'll be glad to get rid of that Corsair because to be honest I haven't trusted it since last time it went pop.

Do you know if the 'Antec True Power New 650W Modular Power Supply' would be a good replacement? One of my major requirements for the PSU is for it to be as quiet as possible and the Antec one got reviewed well by SilentPCReview.
 
Thanks for the reply, I don't know anyone that I could borrow one off so I'll probably just buy a new PSU on Monday which will allow me to check if it's the PSU or not. Even if it's not I'll be glad to get rid of that Corsair because to be honest I haven't trusted it since last time it went pop.

Do you know if the 'Antec True Power New 650W Modular Power Supply' would be a good replacement? One of my major requirements for the PSU is for it to be as quiet as possible and the Antec one got reviewed well by SilentPCReview.

Oh yes, Antec are a very good brand and that PSU is an excellent choice. You shouldn't have any problems with that : )
 
You may well be ahead of me here, but before buying a new PSU make sure you check your kettle lead and/or fuses and surge protector. The initial 10-15 second boot could feasibly have been due to residual power within the PSU and the motherboard will have onboard batteries, but obvious if any of the above have blown the PSU can't draw any power.

Just my 2p, and may well amount to nothing.
 
Out of interest I just unplugged most bits (HDD, DVD, RAM, Graphics), if you push the power button now the fans spin for 10-15 seconds but then it turns off (and back on for 10-15 seconds, and off again in a loop - nothing shows on the monitor).
 
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I left one stick of RAM but not the boot drive (it should boot / enter bios without a HDD connected shouldn't it?)

Edit: I tried a different stick of RAM, this time it booted, let me access the BIOS, worked for about 60 seconds but then shut down.
 
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have you tried the each single stick of memory in each slot ?
Yeah, I tried various RAM configurations, they all seemed to boot for 30-60 seconds but then shut down.

I also just put it back together exactly how it was originally (when it wasn't powering on at all). This time it booted into Windows for about 2-3 minutes but then the the back case fan turned off so I shut it down. Strange :confused:
 
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