Help with system not booting

[KaiHongTan]

Dear PCMR Masters, my pc is not starting up after the house's power got tripped due to a lightning strike. Only a sb_pwr led is blinking when I turn on the power supply, nothing happens if I try to boot. 

Troubleshooting steps I've done

- unplug everything except cpu, motherboard, ram

- jump start power supply to make sure it's not dead

 

So far I think some part of the motherboard got fried, hoping that it didn't fry the cpu as well, what should I do now? 

*Edit - The motherboard is an Asus H170 Pro Gaming and my cpu is a i5 6400

[ArsStudio_YT]

8 minutes ago, DogeGamingPROYT said:

Dear PCMR Masters, my pc is not starting up after the house's power got tripped due to a lightning strike. Only a sb_pwr led is blinking when I turn on the power supply, nothing happens if I try to boot. 

Troubleshooting steps I've done

- unplug everything except cpu, motherboard, ram

- jump start power supply to make sure it's not dead

 

So far I think some part of the motherboard got fried, hoping that it didn't fry the cpu as well, what should I do now? 

*Edit - The motherboard is an Asus H170 Pro Gaming and my cpu is a i5 6400

 

The first troubleshooting step would be to unplug everything and use another similar motherboard to check for damage. Btw is it posting or not? because if not, you prolly have a dead mobo.

Additionally, get a decent UPS to prevent future damage. 

[KaiHongTan]

1 minute ago, ArsStudio_YT said:

 

The first troubleshooting step would be to unplug everything and use another similar motherboard to check for damage.

Additionally, get a decent UPS to prevent future damage.

Thanks for the quick reply, but I don't have another board lying around to test it on, I could get a new one but I'm scared that if the cpu is also fried it will break the new motherboard as well. 

[KaiHongTan]

I also found out that the blinking led is due to overcurrent on the 5v DC standby power rail, which might be caused by shortage or something fried on the motherboard, or simply the 5v standby power on the psu has some problem, but since the rest of the psu is fine I'm 90% certain that something is wrong with the board. 

[KaiHongTan]

But I've yet to try it out with another power supply as I also don't have another one lying around. 

[ArsStudio_YT]

3 minutes ago, DogeGamingPROYT said:

Thanks for the quick reply, but I don't have another board lying around to test it on, I could get a new one but I'm scared that if the cpu is also fried it will break the new motherboard as well. 

 

If your system is not even posting, it most likely has got nothing to do with the CPU and everything to do with the motherboard. Plus, damaging the motherboard with a faulty (but compatible) CPU is very unlikely, unless it was shorted (which could potentially blow off the voltage regulator) and I don't think a simple power outage could short a CPU. 

 

Bottomline: I think you should first borrow a motherboard from some PC hardware dealer. They mostly have many lying around.

[ArsStudio_YT]

1 minute ago, DogeGamingPROYT said:

But I've yet to try it out with another power supply as I also don't have another one lying around. 

 If your mobo has a power indicator light, and it is turning on when you plug in the psu (double check if turned on) the psu is fine, it's definitely something else.

[KaiHongTan]

11 minutes ago, ArsStudio_YT said:

 

If your system is not even posting, it most likely has got nothing to do with the CPU and everything to do with the motherboard. Plus, damaging the motherboard with a faulty (but compatible) CPU is very unlikely, unless it was shorted (which could potentially blow off the voltage regulator) and I don't think a simple power outage could short a CPU. 

 

Bottomline: I think you should first borrow a motherboard from some PC hardware dealer. They mostly have many lying around.

Alright, I think i know what I should do now, thanks a lot. 

[BlueChinchillaEatingDorito]

4 minutes ago, ArsStudio_YT said:

 If your mobo has a power indicator light, and it is turning on when you plug in the psu (double check if turned on) the psu is fine, it's definitely something else.

A failed PSU can still power a board for an indicator light to turn on. If the light blinks or is very dim (not because the LED itself is bad), it's a dead giveaway the PSU is toast. I'm assuming when OP mentioned that the "blinking led is due to overcurrent on the 5v DC standby power rail", that's from Dell's own service manual. If that's the case, I wouldn't even bother with that unit before the 5V standby circuit really goes out of wack and blows up everything that's connected to it including keyboard, mouse, CPU, etc. Nasty cheap PSUs in the past with faulty 5V standby circuits like BestTec PSUs were notorious for that.

[ArsStudio_YT]

5 minutes ago, BlueChinchillaEatingDorito said:

A failed PSU can still power a board for an indicator light to turn on. If the light blinks or is very dim (not because the LED itself is bad), it's a dead giveaway the PSU is toast. I'm assuming when OP mentioned that the "blinking led is due to overcurrent on the 5v DC standby power rail", that's from Dell's own service manual. If that's the case, I wouldn't even bother with that unit before the 5V standby circuit really goes out of wack and blows up everything that's connected to it including keyboard, mouse, CPU, etc. Nasty cheap PSUs in the past with faulty 5V standby circuits like BestTec PSUs were notorious for that.

 I assumed that he was using a good quality power supply that has multiple security measures and turns off automatically in case something goes wrong. Most of the recent ones do that. But then again, nothing is safe from Murphy's law.

[BlueChinchillaEatingDorito]

Just now, ArsStudio_YT said:

 I assumed that he was using a good quality power supply that has multiple fail safes and turns off automatically in case something goes wrong. Most of the recent ones do that. But then again, nothing is safe from Murphy's law.

Correction: I don't even know why I was thinking of Dell when I wrote that. 

[KaiHongTan]

5 minutes ago, BlueChinchillaEatingDorito said:

A failed PSU can still power a board for an indicator light to turn on. If the light blinks or is very dim (not because the LED itself is bad), it's a dead giveaway the PSU is toast. I'm assuming when OP mentioned that the "blinking led is due to overcurrent on the 5v DC standby power rail", that's from Dell's own service manual. If that's the case, I wouldn't even bother with that unit before the 5V standby circuit really goes out of wack and blows up everything that's connected to it including keyboard, mouse, CPU, etc. Nasty cheap PSUs in the past with faulty 5V standby circuits like BestTec PSUs were notorious for that.

The led is definitely bright. The statement about the overcurrent is what I found online from other Asus boards troubleshooting forum threads, the Asus manual only states that it should be on or off, nothing for blinking, that's why I assumed that it was the case as well. Not 100% certain though. I'm using a g750m from cooler master. 

[KaiHongTan]

Probably when the lightning struck the power surged or something that damaged it, before this other electrical trips didn't do any damage, I'm pretty certain something has to do with the lightning strike. I do have a decent surge protected power strip. And nothing else connected to it got damaged. 

[ArsStudio_YT]

1 minute ago, DogeGamingPROYT said:

Probably when the lightning struck the power surged or something that damaged it, before this other electrical trips didn't do any damage, I'm pretty certain something has to do with the lightning strike. I do have a decent surge protected power strip. And nothing else connected to it got damaged. 

Are you able to boot into the BIOS setup utility?

[BlueChinchillaEatingDorito]

6 minutes ago, DogeGamingPROYT said:

The led is definitely bright. The statement about the overcurrent is what I found online from other Asus boards troubleshooting forum threads, the Asus manual only states that it should be on or off, nothing for blinking, that's why I assumed that it was the case as well. Not 100% certain though. I'm using a g750m from cooler master. 

Yea I'm going with their recommendations. It's either a damaged PSU or board. If you have a spare PSU it'll be easily to definitively check. Doesn't even need to be a powerful PSU. Even a 250W will do nicely if you have one. Just remove the GPU and boot off the onboard graphics. (Just for diagnostic purposes).

[BlueChinchillaEatingDorito]

Just now, ArsStudio_YT said:

Are you able to boot into the BIOS setup utility?

If it's not starting up, I'm assuming it doesn't even POST or show signs of life apart from the standby LED.

[KaiHongTan]

Just now, ArsStudio_YT said:

Are you able to boot into the BIOS setup utility?

I can't even get it to post, when I switch on the power supply only the led that I mentioned before blinks, which it normally shouldn't. Pressing the power button absolutely does nothing. 

[KaiHongTan]

3 minutes ago, BlueChinchillaEatingDorito said:

Yea I'm going with their recommendations. It's either a damaged PSU or board. If you have a spare PSU it'll be easily to definitively check. Doesn't even need to be a powerful PSU. Even a 250W will do nicely if you have one. Just remove the GPU and boot off the onboard graphics. (Just for diagnostic purposes).

Yeah for now I'm just looking for another psu to test out. If its not the psu then I'll just swap out the board