Bizarre power problem mystery

Hey everyone, I have a really bizarre problem! It's tricky to explain and it has evolved over time so will bullet point some events but the general issue is that often my PC only turns on when I slowly insert (really really slowly) the power plug into the back. I can appreciate that it sounds like a faulty PSU but I really don't think it is (I wish it was that simple!). I think it's related to my PC being confused about sleep/power modes.

* Sometime in early 2016 I did a major update on my desktop PC. New EVERYTHING (including upgrading from Windows 7 to 10) apart from PSU and Case. When I put all the pieces together I really struggled to get it to come on at all. I did the paperclip test on my PSU and it worked fine. Eventually I had to bring it into a shop, it worked straight away for them. No idea why. Took it home, it worked fine.

* After 3 or so months I started to have issues where it wouldn't turn back on after powering off. I would open it up, take out the power cables including those tiny front panel ones. Eventually messing around with these would get it working again. This kept repeating.

* Eventually it just didn't power on. So I took it back to the repair shop, when I picked it up again they said some internal power cables were loose and it now works fine. Took it back and all was good for a few weeks and then the same was happening again. I figured it was time for a new case, perhaps the front panel connections were loose and old? So they rebuilt my whole PC into a new case.

* All was good for about 3 weeks and it started happening again though this time I've not opened the case. I find that slowly inserting the power plug does the trick.

* Now, this is the most important part. The issue I am about to describe has been happening ever since I upgraded my parts and moved to Windows10. I think there is some major conflict going on with the power settings. I will hit 'sleep' and if it's more than a few hours when I come back it sometimes doesn't awake by tapping keyboard/moving mouse. Then when I insert the plug it doesn't restart but 'awakes' from sleep mode! Sometimes I will 'shut down' and then come back, tap the keyboard/mouse (not remembering I shut down) and it will awake from sleep. I think that there is a conflict with my desktop power setup and Windows 10? I've never updated my Bios, could be that?

Thanks to anyone who made it this far



and here is some info if useful;

Yeah I did try using the same power cord on my monitor and my monitor came on fine. I tried using the monitor power cord on my PC when it wouldn't turn on and it still didn't power up so I really don't think it's the cord. I installed speccy, is a screenshot good for you?

I believe it's this one;



I also found some more power settings, curious about the 20min hard drive setting. Does that seem odd?

Could it be my PSU is not that compatible with my new parts? Underpowered?

Yes, think I'll look into updating BIOS first as I don't have an extra PSU around. Here are a list of BIOS updates, tempting to get latest but that's a BETA which concerns me. Do you really think any of these could make a difference to the way the system powers down?

Recently I managed to power off twice and come back hours later and be able to power it on with one single click of the power button. Then I tried this morning and it wouldn't come on, had to pull/push plug about 20 times whilst tapping the power button to get it to come on again. I've managed to update my BIOS with success, though as soon as I updated it and exited the pc wouldn't turn on again which was scary! This time it took even longer, about 30 pull/pushes of the plug whilst tapping the power to get it going again.

Will have to see how it plays out but I have no confidence that this BIOS update has made any differences. How about drivers? Could any of these make a difference? I think ultimately I need to buy/install a new PSU just to rule that out. Which is a pain but I can't imagine it being anything else other than a weird conflict with Windows and motherboard.

Yeah will check next time I open it up. Would be unexpected, the board is only about 5 months old.

I put pc in sleep mode, then couldn't get it to come back on again. Had to fiddle around with power again to get it to come back on. That's something I've noticed and not mentioned yet, when I put PC to sleep there are no LED lights on or any sign of power but from what I remember in the past you should have some form of LED light/sign of power in sleep mode yes?

Sort of figured this out finally, left it at a shop and they said it came on every time! Took it home, tried it in the kitchen and it worked. Tried it in the usual office area and it didn't. Started unplugging other devices and it worked. Plugged them in and it wouldn't etc. So it's something to do with my apartments power supply? too much power on a circuit or something?

Yeah I do have an update, it seemed fine for a few days but it has come back again. Sometimes it won't turn on, so I unplug everything and take it to another room, sometimes that can get it going again but not always. Right now the best method is to HOLD the power button it whilst clickiing the back I/O switch on and off a few times. After coming back from the repair shop I really thought it might be a circuit overload problem but it's not because if it doesn't power on, unplugging other things doesn't resolve it.

It really is the most horrible ghastly kind of PC problem I've ever encountered. I wish something was just broken, like the PSU but obviously it isn't that. I can take it into a repair shop but as I've said, works fine for them so that's useless.