XPS 8920, power button hard to start

Finicky power button that is getting harder and harder to start system is telltale sign of failing psu.  Use a spare working 24/4 pin psu to confirm suspicion.  If yes time to replace or upgrade stock psu.

I'm guessing psu is power supply unit? Is that where the power cord plugs into the back of the tower?

Have you tried using the PSU test button on rear of PC to do the BIST test?

Some users have lightly sprayed some electrical contact cleaner into the power button module and that helped with this issue. So if it helps here, you'd know to replace the power button module which is less expensive than a new PSU...

I haven't tried that. I will though. I guess I could just leave it powered on and cross my fingers that it would restart after a power outage. We never turn our pc's off at work.

Of course this would happen 4 months after the warranty expires. I guess if it does need a new power button or PSU I could get it switched over to Windows 11 at the same time it was in the shop. Lots of options to consider but definitely the wrong time of year for it to happen.

What looks "fairly easy" to the computer confident scares me to death. There's no way in this world I would attempt to take the covers off of this unit and start fiddling around in there. Same goes to update it to Windows 11. If there's something that could go wrong, it would go wrong with me. Nope, I'll let it do it's normal Windows updates when they're due but that's as far as I will go.

@Jezza819  Looks fairly easy to remove the power button module if you want to DIY. Instructions are in the Service Manual.

If nothing else, use those instructions to ID the button module and do a light spraying into it with electric contact cleaner, being careful not to let it drip on any other surfaces. You shouldn't even have to remove the module or its cables or anything else, just to spray it. Then close up and with PC unplugged, press/release the power button a few times. Then plug PC in and see if that solves the problem, at least for a while.

If contact cleaner doesn't help at all, that doesn't necessarily mean the module isn't the problem. So in that case, try the BIST test to see if you can narrow down the list of suspects...

You shouldn't need a "shop" to update to Win 11. Windows Update will handle all of it for you. Always a good idea to make an image of the drive and store it on external media before doing an update like this, to be safe...

Good a geeky friend who can spray the power button module for you?

Updating to Win 11 via Windows Update shouldn't be any different than letting Windows Update do "routine" updates. You could image your boot drive with Win 10 first and store the image on external media, just in case. Besides, it's always prudent to back up your files anyway.

Macrium Reflect is free and very easy software for imaging a drive and there are lots of free online tutorial guides for it too.

Kind of. There's a place a little outside of town that has worked on my laptop before so I'll take it to them. But it will have to wait until after the holidays. I'll just leave it powered on for now. 

Re: There's no way in this world I would attempt to take the covers off of this unit and start fiddling around in there.

that is fair enough.  what seems easy to people who have worked on inside pc can seem intimidating to others.  Ask me to open my car hood and touch parts inside.  no jose.

psu does mean power supply unit.  testing motherboard using a spare working psu is not a trivial procedure.  good thing is if the psu is dying, it will most likely pass away quietly.  keep pc powered on now is good idea.  I do not trust the Dell BIST procedure too much.  At the end of day, if a good psu can make your pc turn on instantly with a simple push of power button each time is good enough proof that the old one is no good.

@Jezza819  I'd back up your personal files (or image the drive) asap, to be safe. If it gets shut down and won't restart, at least you'd still be able to access your personal files from your backup...

My 8920 has exactly the same problem. I’ve concluded from the power supply test (though I could be wrong) that it’s my PSU that’s going bad and not the front button. I have to keep playing with it (unplug & plug cord, press the test button, which powers up the fan) to get the green light to come on long enough for the front power button to work when pressed and the PC to boot.

I bought an exact replacement PSU, went to install it yesterday, and was stopped in my tracks – can’t reach the socket that powers the CPU; it’s covered by the CPU cooler, which I can’t figure out how to remove. (Yes, I know in principle, remove the screws and pull it off, but it’s unusually shaped and in a cramped space, and it’s not obvious how to get it out without damaging it.) Time to start looking for a new desktop to replace this 4-yr-old PC.

Have you checked the XPS 8920 Service Manual for instructions to remove/replace the PSU? There's no mention of needing to remove the heat sink.

If you do remove the heat sink, you have to make sure not to pull the CPU out of its socket.  And you have to gently clean old thermal paste from top of CPU and bottom of heat sink, apply a thin coat of fresh thermal paste and then re-attach the heat sink on the CPU.

I turned off computer before vacation by pressing and holding power button.. Will not start up -now.Dell XPS 8920 - self test in back works with light and power to fan. Will try electric contact cleaner - if it doesnt work should I replace module or bring it to place for service

@simapc  I'd replace the motherboard battery first, especially if it hasn't been replaced in a while.  See here.  If nothing else, you'd rule the battery out for only ~$2.

Is the power button for the desktop xps 8920 male to male or male to female?