Undeerpowered PSU damaged pc?

GeekFixUK · May 8, 2019

Hey guys, long time follower, first time poster

Ive got a pc in that is frustrating the hell out of me. A list of the specs before i start:

Intel i7 8700

Asus z390-a motherboard

Hyper X (hx432c16pb3k2/16) 16gb ram Dual Channel Kit

Evga GTX 1080 FTW

corsair h100i rgb watercooling

Samsung evo 1tb ssd

3 120mm case fans

and the kicker, corsair vs550 power supply.

Now my friend brought me the pc saying that it still boots but no video on screen. This happened after a night of heavy gaming. I immediately noticed that the psu is not good enough for all the hardware in his pc. The gpu alone wanting a min 500w psu. If hes gaming and pushing the gpu then surely 550w wont cover it. So first and foremost hes dropped off a new corsair rm750x psu off but alas im still getting the same problem.

So ive taken his motherboard out of the case with just the ram, cpu, cooling and psu plugged in. Knowing the cpu has onboard graphics, i reset the bios via the mobo jumper and plugged hmdi into the motherboard. still no video signal.

Tried the same again but alternating ram sticks in alternating b2 and a2 slots. still nothing. Furthermore the motherboard has onboard boot diagnostic lights, they light up quickly and go off in turn, even the speaker ive got on the motherboard jumper doesnt give a fault code. To see if the speaker or motherboard wasn't posting correctly i removed all the ram and booted, sure enough the speaker started peeping the no ram code.

Ive tried with the gtx1080 plugged in and power now on the 750w psu and tried all of the above, still no luck.

To clarify ive plugged my psu tester into the corsair 550w psu and it currently tests fine on all the lines and rails, so it has not blown.

If i remember correctly he said the system was about 4-6months old from new. So im fairly sure its a dead mobo but im just not 100% sure, just because those damn mobo post led's think that everything is ok.

Am i missing something or can an underpowerd psu break a motherboard, cpu or graphics card when its being pushed.

Uptivuptiz · May 8, 2019

2 minutes ago, GeekFixUK said:

I immediately noticed that the psu is not good enough for all the hardware in his pc. The gpu alone wanting a min 500w psu.

GPU manufactures set the wattage "required" for the GPU as the recommended minimum PSU for a system with that specific GPU in it. Look at the TDP for the GPU instead. I think the TDP for the 1080 is 180W.

191x7 · May 8, 2019

I recommend checking the CPU in a different motherboard.

Jurrunio · May 8, 2019

Which Corsair VS, orange label one or grey label one? 550W is enough for a build like that, probably the wattage I'd go for, just not this model. And yes, if the PSU is to blame it could cause permanent damage to the components.

31 minutes ago, GeekFixUK said:

Furthermore the motherboard has onboard boot diagnostic lights

really? Q-LEDs are an ROG feature, the Z390-A doesn't have any as far as the offical site says. Neither do the Z370-A and AM4 socket X470-Pro has them.