PC will not boot after power surge and new PSU installation

Jan 19, 2019
Hello all,

My computer won't boot after a power surge yesterday. I returned from 2 month holiday and turned my PC on. Everything was fine for about 5 minutes, after which a fuse popped in my flat and I lost power in my wall sockets, and some other appliances (lights were still on). I went to the fuse box and turned the switch back on, regained power for my sockets, but ever since my computer won't boot.

I suspected the PSU as the most common issue, I tried the paperclip test and my PSU wouldn't start up, so I ordered a new one off Amazon. I replaced my old Corsair RM850 with a Seasonic SSR-850FX, installed it this morning, but my computer will still not boot.

I don't think my mobo has an in-built system speaker (which is making debugging difficult), and I am still looking for one in all my components' boxes. However, when I press the power button on my case, there is a brief crack in the plugged-in speakers (making me think that the mobo is getting power).

Unfortunately, I don't have any spare CPU / mobo around to test individually, and I'd rather give it some more effort before investing into new components. Any and all help is greatly appreciated!

My specs:

Gigabyte GTX1080
256GB Samsung SSD
16GB RAM Vengeance Corsair
MSI Z97-G45 Gaming Motherboard
Both of your power supplies are very good.
FWIW the paper clip test is useful to confirm a totally dead psu, it does not tell you anything about proper operation.

Can you test to see if your power outlet is properly grounded?
If not, that is the first thing to fix.

At this point, I think the power surge caused some damage.
The most likely victim is the motherboard.
Jan 19, 2019
I tried unmounting most of the hardware from my mobo (tried booting with and without RAM, GPU, CPU), and the PC still won't boot. I suspect it is fried. I tried following some tutorial on youtube for measuring voltages using a multimeter, but any component could be damaged on the board. I'm getting 4.5V on my Power Switch pin connector. 3V on my CMOS battery. These are all values that match the ones in the mobo's manual.

I'm guessing something happened on my electrical network which caused something to burn up on my mobo. At this point I'm just willing to invest into a better PC, as mine is already 6 years old, and most likely buy a UPS for it as well. I'll also call landlord admin to come perform an electrical inspection of the flat, just to be on the safe side for my new rig.


Your parts are still good.
Perhaps you can take it to a pc shop and ask them to identify the bad part/s.
They will have the ability to swap out parts.
Unfortunately, that is about the only way to pinpoint hardware component failures.

OTOH, this might be a good justification to splurge on a big upgrade.


May 20, 2008

Don't forget to include a good quality surge protector with your new build. UPS is an even better idea.


Similar threads



Latest posts