[SOLVED] PC powers off randomly, sometimes won't start

[greymanic]

I've had an HP z400 for several years. It's used every day. Since doing some upgrades it continued to run fine for a couple of months. Now it's started to power off randomly and often takes several tries to power it back up to full boot. He'll be watching youtube or playing Gerry's Mod and you hear a click and it turns off just like someone unplugged it or hit the power button. Sometimes hitting the power button just once will boot it up normally but often it takes several attempts (I press the power button, blue power light comes on immediately followed by the click and goes dark again). If it doesn't power up first try I often have to let it rest for a few minutes and then it will start. Sometimes it will not start first thing in the morning but usually happens after a random shut down. Sometimes it shuts down several times a day, sometimes will go three days before doing it.

I've tweaked the power options in Windows 10 that someone said may contribute to the problem. I thought it could be overheating so I've put new silicone gel on the heatsink and made sure there's enough. I installed a front fan to cool the case better. I tweaked the GPU card's fan with Afterburner to make sure it runs at a higher speed and put a lower min temperature. It's pretty much on constantly now.

Here are my specs. The motherboard and PSU are original. PSU is in range of the new video card:

HP Product code: VS933AV
Xeon x5690 3.47ghz
10 gig ram
Geforce GTX 960 duel fan
475W PSU

 

[Lutfij]

By original, how old is the PSU? The click sound you mention is the circuit turning off to protect itself and the components it's hooked up to, meaning to prevent the PSU from blowing up. You should look for a replacement PSU and see if the issue is averted.

 

[greymanic]

I looked up the serial number and the warranty start date was June 23, 2011. PSU was going to be my next try. It's been 2 days since I replaced the silicon gel and we haven't had a crash yet with almost constant use. You think I should get the PSU so there's no chance of eventual damage to other components or will the safety mechanism prevent that? Thanks.

 

[greymanic]

This is an unresolved thread. Is someone going to respond?

 

[GarrettL]

As stated, your PSU.

 

[greymanic]

As stated, your PSU.

OK. Do you accept followup questions?

 

[GarrettL]

Sure, but when the psu is beyond its warranty date and you have stability issues it's usually the age of the power supply is causing problem.

That pc originally came with a 3 year warranty and if I were to purchase the same power supply today it only has a 1 year warranty.


PC Review;
https://www.tomshardware.com/reviews/hp-z400-workstation,2718-2.html


OEM PSU
https://www.neweggbusiness.com/Prod..._IErZqUjY_BQugiVbn8aAqvCEALw_wcB&gclsrc=aw.ds


I retired my old x58 pc from gaming last year, same era as yours. Even though it was running fine I replaced the old psu. If a psu fails in a bad way it can take out other components with it. Better safe than sorry.