Power switch intermittent

[Martin_67]

I'm trying to determine what exactly is causing my pc to fail to power up intermittently and I'm caught between the powerswitch and the psu. At first this manifested itself by not turning on when I pushed in the button, I would only get power if i pushed it umpteen times.

Now I'm essentially having to jump my motherboard pins each time I want to turn on my computer however the power switch still intermittently works from time to time if I flick the mains off and on again.

I'm at a loose end because as soon as I jump the mobo my system appears to run fine for hours and I've been playing games and all sorts with it.

I've tried swapping the reset and power switches to no avail and I'm convinced now that this has to be coming from the psu which I have had running stable in my current build for several months now.

any help appreciated

 

[Lutfij]

1| Can you please pass on your full system's specs inclusive of your OS?
2| Have you made sure your BIOS is up to date?
3| If you're sure it's the PSU, have you borrowed a reliable, branded unit from a friend to power your system and verify that the case buttons aren't at fault?
4| It'd also be a good idea to verify that the system works when it's outside the chassis when bread boarded, it may be a grounding issue with the cases buttons.
5| Might also be a good idea to inform us of your warranty status, since you may or may not be eligible for an RMA.

 

[Paperdoc]

You say it always works if you "jump the motherboard pins". What pins? The same two that the front On / Off pushbutton is attached to? If so, the surely this proves that the PSU is working just fine because that always works. It confirms that the pushbutton switch is the problem.

If that is the case, I'm surprised that substituting the Reset pushbutton switch did not solve the problem, but so be it. This switch is a very simple normally-open, temporarily-closed switch that only connects its two contacts when it is pushed in, and opens again when released. Just like any simple doorbell pushbutton. So you could get any switch of that type, connect it to the mobo pin pair, and verify that a new switch works reliably. Then you would know exactly what to replace.

If that verifies that a switch replacement is your answer, you might find it hard to get an exact replacement for your front panel. But even something that looks reasonable and can be mounted on the front will do OK.

 

[Martin_67]

I've bread boarded my system and it works fine only after I've tried shorting the powerswitch header again. Although it is taking a lot longer to power on that it has before this method is still the only way I can get my pc on at all. I've contacted my case supplier and I've received a replacement power switch from them and still to no avail.

So I'm certain now it's not the switch. Moreover I have swapped the psu with an older but trusted unit and it now boots up first time I push the button. Usuallu at this juncture I would just buy another psu because all evidence points to it being the source of my trouble, but I can't understand how I can run my system smooth for hours on end once I've shorted the pins.

My faulty unit is an XFX 750W XXX Semi Modular that I've had for roughly 4 and a half years. It's out of warranty with the supplier I know but as far as XFX go their process isn't the most customer friendly or very straightforward.

In all consideration if it is easier and quicker to simply buy another psu then that's what I'll do


I haven't tried updating my bios yet

My system specs as follows;

Windows 10 64bit
i5 4690k @ 4.2ghz
GA-Z97X-SL
ocz vertex 4 128gb ssd
500gb hdd
16gb x ddr3 1333mhz
gtx 970


cheers