I decided to clean out my CPU fan as it was clogged, when I assembled everything again it won’t turn on 🙁
It’s an old desktop PC. There are no lights glowing on the motherboard at all, though there is none specifically labelled “power”. Just CPU, RAM, BOOT. None of these light up, not even a flash when it starts.
I have reseated the RAM, CPU, power cables. Removed the GPU to check.
The cord leading in to the PSU works but I don’t have a way to test the PSU itself or the out cables, but I have reseated them at each end.
This PC was working fine before. But with no lights on the motherboard I suspect either the mobo or PSU?
Mobo is asrock x570 PSU is silverstone 650w strider gold S series
Any help appreciated!
Edit: I made a new post asking for hardware recommendations.
Edit 2: I managed to get a light on the motherboard, going to buy some more thermal paste and keep tinkering to see if I can get it started!
Edit 3: I never got that light to go again. In the end the comments on the other post convinced me that I had all that I needed for what I wanted (no upgrade needed), so I changed tack to seeing how to fix it. I had suspicions about the power connection still, so I bought a cheap PSU and tested it, no change. Then I bought a new motherboard (also a pretty cheap one, the cheapest that had what I needed and was also in a local store) and in the end that was the issue. Everything is up and running again now! Thanks for all the help everyone, you can now settle your bets.
It’s an old desktop PC
One (or more) of the electrolytic capacitors in your PSU has died.
Remove the power cord, wait for 2 hours, open the PSU and look carefully for the candidate(s) with the domed head. Healthy ones are perfectly flat on the head.
Order a new one and replace it.
I did a paperclip test, PSU seems fine.
What did you do?
What did you expect?
What did you observe?
I followed someone else’s instructions. Expected putting a paperclip in in and plugging it in/turning it on would cause the fan to start up. It did.
https://robots.net/tech/how-to-power-up-psu-without-motherboard/
Fan in PSU started up fine, apparently this is a sign that the PSU is not dead. Fan does not turn on when connected to the motherboard, which supports the theory that the PSU isn’t the issue.
I had this exact issue on an old gaming PC, PSU wouldn’t power the MB, but would be fine by itself. My GPU had a short, gods know how it happened. Juts keep disconnecting parts and try powering up again until you get the LED indicator. If everything is gone and it still won’t power on, it’s the MB. You could get a multimeter and measuring the power lines to see if there is a short (5V to ground, 12V to ground and I think there are 24V lines?). Maybe look for burst or burned capacitors and if you’re crafty and able to solder replace them. Otherwise replace the MB or defect parts.
I’m leaning toward a short somewhere, since you said the PSU starts up with the paperclip but not when plugged in to the board.
I bought a multimeter and tested the PSU, and it all seems fine. So pretty sure it’s the motherboard or CPU.
I’m using it as an excuse to do an upgrade, so will probably get a new mobo/CPU/RAM.
Does the power supply work
Yip. Have tested the PSU with a multimeter and it’s fine. Narrowed it down to the CPU or motherboard. I decided I’ll just do a bit of an upgrade and get a new CPU, motherboard, RAM.
Have you tried turning it off and on ag- oh.
In all seriousness, maybe a blown capacitor of any kind? You describe the PC working fine ‘before.’ When was ‘before?’
There is no obvious damage on the motherboard, capacitors look fine.
“Before” was immediately before I turned it off and opened it up to clean out the dust. It was being actively used as a server.
Did you maybe unseat the tiny power switch/activity led front panel cables?
I’ve tried just directly shorting the power switch on the mobo to rule out issues with the case switch, but that didn’t help.
Well, reading this and the rest of this thread, I can’t think of anything else. Since you ruled out pretty much everything else, I would now put my money on one of the parts shorted during cleaning… anecdotally I’ve heard parts dying by shorting them with your fingers, but it never happened to me, so that would be pretty unlucky.
Last time I did a cleaning of a particularly dusty system, a dustbunny flew in the PCI-e port without us noticing (it was dark and circumstances were not ideal). With the GPU Re-inserted, that was enough for the system to behave similarly to yours, but you re-seated everything so… That would eliminate this as a possibility.
You could share a photo of the current situation, a top down of the mobo? Eliminate chances you are missing something by secondary means(as opposed to just text)?
Sure thing, here’s a photo:
It’s sitting inside the case but not installed, no cables connected, Edit:
RAM is out.RAM is right there in the photo 😅 . I left CPU in because I don’t want to have to do that one yet again 😆This photo makes it look quite dusty haha, but this is after cleaning!
You haven’t followed the proper tech troubleshooting ritual:
- Yell at it
- Ask nicely
- Blood sacrifice
- Lament
- Instigate violence (hit it)
- Completely disassemble and rebuild it
- It inexplicably works fine
- ( ◡̀_◡́)
Well I got up to step 6, not sure how to get to the next step…
Addendum to step 7: if it doesn’t work fine, go back to step 1.
- Is the PSU switch on
Is the power switch on the PSU flipped on? Are the front panel wires seated in the right places on the motherboard?
Those are the two that get me when reassembling. I used to have an asrock 320m that had absolutely no grip on the front panel wires and it was easy to unseat one when blowing air into the case.
I’ve flipped the PSU switch both positions, doesn’t really work either way.
I’ve reseated the case power switch cable but it didn’t help. I also tried shorting with a screwdriver in case it was the switch, but nothing 🙁
You mentioned a buzzing in another reply. That sounds like a grounding issue to me. Any chance you blew something under the board that is causing a short? At this point it would be wise to do a full tear down.
I’m almost at my train stop, so one final question before disappearing for the day: when resocketing the CPU did you put it in correctly and was there damage when you removed it initially?
Yeah I will probably do an out of case, mobo, RAM, CPU, PSU only at some stage tonight to test.
Yes on the CPU damage, some bent pins on a corner, but I straightened them and it went back in fine. I had assumed the CPU light would be glowing (or not glowing) if that were the issue, but I’m no expert. Maybe it is the CPU. Expensive to buy one just to test though!
Edit: oh and the buzzing is from the PSU, when off, and not connected to the PC at all.
These lights and beep sequences aren’t 100% reliable. So I wouln’t take it for granted. But it’s a bit suspicious in my eyes that none of the LEDs light up. Maybe it’s the PSU, then? I mean it could be anything. And in my experiences it’s most likely a cable that got unseated accidentally by the vacuum… But you mentioned it’s a server… And I’ve had PSUs fail after being online 24/7 for years, and then one day you turn off the power and they won’t ever come back. And with the bent CPU pins I’m not sure. Most of the times straightening them works, but sometimes they break off after doing that.
These kinds of diagnostics are next to impossible without some spare parts, to swap one at a time and see which is at fault. If you don’t figure it out by chance, you’d need to borrow some.
I’ve done a paperclip test, PSU fan starts up, but doesn’t when plugged into the mobo.
I have now done an out of case test, with CPU, RAM, mobo, PSU, and no luck.
I guess that means mobo or CPU is the issue. I would think if it were RAM the symptoms would be different.
I took the CPU out yet again, all the pins look fine. They didn’t get munched being inserted the last time, so it seems they straightened OK. But at this point it has to be CPU or mobo, surely.
It does seem like that.
(Be sure to thank the kit for its years of service)And if you triggered any failsafes they would have reset by now.
The mobo button battery can rarely make seem the mobo dead, but usually still does at least something.
(I’m not saying it’s likely, just that it’s the last thing I can think of)It wasn’t that many years, I checked and I got the whole setup in 2019. A little over 5 years. It hasn’t been running as a server for that long, perhaps only 6 months. Seems like a premature failure. I probably messed it up by doing something wrong when cleaning. Static maybe? There isn’t anything obvious on the board that l can see, no burn marks, no ozone smell. I guess I’ll look at ordering a new mobo and then new CPU if the mobo doesn’t work. Annoying though, because if I have to get a new CPU I probably want an upgrade, but if it’s just the mobo probably not.
Thanks for the help 🙂
Agreed. And I’d say the mobo is more likely, as it has more different components like capacitors and whatnot. So just by volume.
As a final test you could rip out RAM, GPU etc disconnect all unnecessary cables and run just mobo + CPU + PSU. See if it beeps/lights up or changes anything. That’ll rule out a short in some other component being the issue.
I mean we’re not 100% sure, but looks like you’re in for a new mobo (+CPU).
I already removed all cables and extras when I did the out of case test, didn’t think to try without the RAM. I will give that a go tomorrow, I’ve had enough for tonight,
It looks like I can still get a mobo that supports the socket, so in theory I should be able to just swap the mobo. But then if it doesn’t work I’ll have to get a new CPU next and then I’ll wish I didn’t get the mobo because I’ll probably get a more recent CPU. Hard choices!
For the moment, I have requisitioned a laptop and booted from the server hard drive, and things are back up and running. So I don’t have to rush, I’ll try some more tomorrow, have a think about what I’d like. Maybe I’ll just get something new, and auction off the mobo, CPU, RAM online $1 reserve and someone else can work out what does or doesn’t work . 😆
Did you flip a power switch on the PSU at some point, perhaps? (Done that one a few times myself…)
I’ve tried in both positions.
Might sound weird but I can hear a quiet buzzing in the off position (O) and silence in the on position (1). But I don’t have another to check what’s normal.
It’s generally the reverse thing that happen you can hear the buzzing when on and not when off… 😁
That’s why I mentioned it! It seems logical. Normally 0 is off and 1 on, right? I tried in both positions but it buzzes when in the 0 position.
This sounds illogical to me
For the record, I did a paperclip test and the PSU seems fine. 1 is definitely on, 0 off, and the buzzing is when it’s off 🤷. It’s not loud, you can only hear it when held up to your ear.
And when you unplug the power it goes?
Yeah, may just be that the PC isn’t drawing power, the buzzing might go if it was.
Is there any chance the buzzing is actually from what you have the PSU plugged into? I think ive had a surge protector that have a buzzing without anything drawing power that went away once something was consuming power.
Mind trying another power socket just to eliminate potential environment problems?
Have you tries unpluging it and plugging it in?
One thing that was only mentioned briefly by someone else is the physical button turning on the computer.
Similar to the paperclip test figure out where the power button goes into the mainboardw and bridge that with a short cable. Is possible that by moving the case the old button lost a cable.
This is just one more thing to test though, it’s really trial and error as you know :)
One of the first things I tested 🙂. I’m almost ready to give up, buy a new mobo/CPU/RAM and then auction the old stuff off online for someone else to work out what does or doesn’t work 😆
How does everyone have spare parts to try, it seems almost every generation you have a new CPU socket and new RAM type so you can’t use the old stuff!
I’ll probably be asking for hardware recommendations soon haha
it seems almost every generation you have a new CPU socket and new RAM type
I bought AMD, and I keep old computers around. Here’s my progression so far:
- AM3 CPU as my desktop PC
- AM3+ CPU as SO’s desktop PC
- AM4 CPU to replace 1 (OG Ryzen), 1 becomes NAS
- AM4 CPU to replace 2 (Ryzen 5000), 2 is hot spare
- AM4 CPU upgrade (Ryzen 5000) to replace 3, also got mobo to replace NAS
So, if I needed to, I could:
- downgrade to AM3+ CPU, using DDR3 RAM from either build (or both)
- upgrade my or SO’s computer to AM5 and reuse desktop for NAS
For extra parts, I have:
- 1 PSU
- 1 GPU - GTX 960; GTX 750 Ti is in NAS
- 2 CPU/mobo combos for AM3 and AM3+
- 2 computer cases - one is trash though, I’ll throw it out soon
- various cables and whatnot
If I was doing this solo, I’d still have my old mobo and CPU, so I could at least downgrade to that.
I think your advantage is needing two machines. Then you can swap stuff between them to test as well.
I gave away my previous build in whole and built a new one. No spare parts 🙁. And my SO and I are generally using laptops day to day, no need for more desktop machines and can’t swap pieces between laptop and desktop.
I don’t think having an old mobo/CPU would help anyway, I’m pretty sure one of the two is broken and swapping both out won’t help work out which one.
Sure, but even without a P2, reusing the old PC when upgrading was the main thing. I haven’t actually used my SO’s computer for anything yet, it’s just a hot spare should I need anything.
I honestly can’t use a laptop as my main machine because I (and my SO) play games, and using a laptop would mean a lot more frequent upgrades. I have a laptop, but it doesn’t need very high specs since it’s just for trips (mostly videos and web browsing). My laptop is ~6 years old and still does everything I need it to, whereas I upgraded my desktop three times in 7 years (CPU twice and GPU once).
If you had an old mobo and CPU, you could downgrade and keep the NAS running until you had a replacement. I upgraded my NAS because I already had the hardware and wanted better power efficiency, so I could totally go back if I needed to. In my case, I’d downgrade until I upgraded my desktop, then re-upgrade my NAS. I’d probably use my SO’s old machine, but it works with any spare PC.
I don’t do a lot of gaming these days. When I played Baldur’s Gate 3, once I got to Act 3 I switched to streaming from the desktop to the laptop using the Steam function as my laptop couldn’t handle it. I also don’t do upgrades as frequently as you.
If you had an old mobo and CPU, you could downgrade and keep the NAS running until you had a replacement.
Good point, I didn’t think of that.
I don’t do upgrades very often either. Here’s my rough history:
- Phenom II full PC (no GPU)
- GTX 750 Ti - wanted to play games
- GTX 960 - SO needed a PC but didn’t play games, so I upgraded mine
- Ryzen 1700 + mobo + RAM + nvme drive - CPU was severely lagging - 1 became NAS
- RX 6650, Ryzen 5600 + mobo + case - GPU was lagging and the 1700 couldn’t sleep (CPU fault), so I figured it was time to upgrade; 4 became NAS
I’m still using 5 today, so in 10-15 years, I had 3 GPUs (gave 2 to SO when I got 3), 3 CPUs, and 3 mobos, and I only upgraded the mobo in 5 because I wanted to reuse my 1700 in my NAS. My NAS currently has 2 & 4, and 1 & 3 is a hot spare if anything dies.
In that time, I’ve had 3 laptops:
- HP POS for school (forget the model)
- Thinkpad T440 - 2013 - HP fell apart
- Thinkpad E495 - T440 died from water damage
1 & 2 are e-waste and cannot be reused.
If you don’t count my SO’s devices, I think I’ve spent about the same on laptops as desktops, and my laptops have been very budget devices (no dGPU), whereas my desktops have been pretty midrange and I’ve been able to play whatever I want.
I’m thinking of giving my kids a PC, and if I do, it’ll be my SO’s old PC. If I do, 3/4 of our PCs over the past 15 years will still be in use vs 1/4 of our laptops (SO had a laptop that died before I built the first). That’s a pretty good track record IMO.
I use a laptop most of the time because then I can sit in a recliner with my feet up. I spend the day at a desk I don’t much fancy doing the same in the evening.
I have a Framework laptop from the first ones they made, which are upgradeable and repairable. Unfortunately they don’t ship to NZ, I got mine by freight forwarding and also got parts a bit later the same way. But now they have cracked down hard on freight forwarding as I recently learned, so I can’t get any more upgrades until they start shipping here (no announced plans).
Did you use compressed air to clean out the fans?
It’s possible to fry circuitry if you artificially rotate the fans too fast, as this generates an electric field more powerful than the fans and their attached components are rated for.
Probably rare to cause damage with modern computers but an old PC might be more susceptible to this type of damage.
I joked the dust was what was keeping the PC running when this happened to me. But your explanation makes more sense. Dang
Not compressed air from an air compressor, just the canned stuff. I don’t think I spun any fans too fast. Plus the PC is only 5 years old.
Compressed air can spin the fans fast enough to cause damage unfortunately.
Probably not this one. I was a little disappointed with how little airflow this can gives me. In any case, I don’t think I spun any CPU fans around much at all.
If you got another psu then that would probably be the simplest way to verify if its the psu or not.
I don’t. No other desktop in the house, no spare parts 🙁
It’s dangerous and you can blew it if you don’t know what are you doing but by shorting two specific pins, it’s possible to turn on the PSU and see it it’s working or not
Did you use a vacuum on the fans and let them spin during the clean?
Not on the PSU fans, and was using canned air cleaning stuff.
Someone else posted a link about testing the PSU. I’ll consider it.
When you tear down next, look for missing board components or any that lean at an angle they’re not supposed to. Canned air has been known to shear poorly-attached caps or whathaveyou clean off the board. Or maybe one of the wires in the 12v cable is broken and it’s delivering power just to most pins… The paperclip test just tells you if the PSU is dead dead, are you able to test with a multimeter instead?
Buzzing while the power supply is off makes me wonder if there’s literal bugs in it, if it’s buzzing while it’s unplugged. I suppose the buzzing could also be remaining power discharging, if it happens just after it’s been unplugged.
I pulled a psu out of my rig over the weekend. I was just going to chuck it on Trademe for $1. Let me know if you need it, though shipping might take a few days.
I did a paperclip test and the PSU seems fine, but thanks for the offer. Got to be mobo or CPU I think.
