Question PC won't start after cleaning it ?

acidblue811

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Jul 21, 2019
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This morning I did a quick clean of my PC (dust with a hand blower, wipe dust on surface, no parts removed aside from side panels). Closed up, reconnect cables, but no start on monitor. The cpu fan was running but gpu fan wasn't. Thought maybe the psu was acting up. Swapped in a spare psu, now nothing turns on. Swapped the former psu and everything is turning on, checked all switches (on).

What might I have screwed up, and how do I test if thats the bad part? Thanks in advance!

Edit: is my motherboard dead?
 
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We need a full list of your components first(include models for every part).

While you're there do another once over for your components, check connections, reseat GPU, RAM.
Hi, thanks for the reply, please see below for the parts list:

CPU: Ryzen 7 (no OC) w/ default fan and sink
MB: Aorus B450 Pro (no wifi)
GPU: TUF 3070
Physix: Gigabyte 1050
HDD: WD Blue 1Tb (OS) + WD Blue 4Tb (apps+games)
RAM: 4x 8Gb Teamgroup
PSU1: Gigabyte 850w gold
PSU2: Silvertec 850w gold (trendy)

Apologies if the specs are light on details, I don't remember and can't find the boxes.

Reseating done, still nothing. Also, not sure if this is new or I just didn't notice earlier, there's a mild electric feel to some metal part of the case when touched. Not painful, just a sort if milc buzzing sensation. Went away after a bit when disconnected from power
 
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Reseating done, still nothing. Also, not sure if this is new or I just didn't notice earlier, there's a mild electric feel to some metal part of the case when touched. Not painful, just a sort if milc buzzing sensation. Went away after a bit when disconnected from power
Sounds like your outlets are not grounded. Gotta be a pretty old house.

Your motherboard should have EZ debug lights when trying to POST(near the front panel pins), does the light get stuck on something when trying to power on?
 
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Swapped psus because i thought the first one was acting up, then when nothing turned on, swapped back to the old one an now nothing turns on
 
Swapped psus because i thought the first one was acting up, then when nothing turned on, swapped back to the old one an now nothing turns on
Ok, gotcha. Try taking the motherboard out of the case, preferably on a non-conductive surface(you can use the motherboard box), plug everything in and test it out like that.

Before powering on I'll advise you to start with the bare minimums: 1 stick of RAM, 1 GPU(try both of them separately), no storage drives. See if you get anything.
 
How do I power up without the case? Not sure I can pull the switch w/o breaking something
Forgot to add that, you don't need the switch from the case.

You need to short these 2 pins with a piece of metal(screwdriver works perfectly) at the same time on the Front Panel of your motherboard:

FuJN1W5.jpg


The power button on your case does the same thing.
 
Okay so did the thing above, used the 1050 and 1 stick. Tried psu1, psu2, and an undersized psu i had lying around, tried to short the power pins with 2 different screwdrivers.

Results:

Indicator light turned on briefly when psu was connected and switched on (happened for all 3, flashed for less than 1 sec)

Nothing turns on when shorted with screwdriver (for all 3 psus, and both screwdrivers, looking for a suitable piece of copper to do round 3)

How screwed am I?

Edit: Tried a piece of copper wire for shorting, no dice
 
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No silvertec brand psu

I was afraid of that. First things first, send that to recycling. It's a junk PSU, faked to look like a Corsair RMx. If that was ever in the mix, then any type of destroyed component is a possibility.

What's the third PSU involved? Our best chances of us solving the case involve us knowing *all* the pertinent facts. And you didn't actually answer the question; did you re-use any modular power cables between the PSUs that use modular cables? Pinouts aren't universal on the modular PSU side, so if you were mixing and matching, the chances that you destroyed one or more components while trying to resolve the issue are very high.
 
The 700 is a seasonic s12 bronze, I know it's good because it was my previous psu before I swapped in the gigabyte p850gm. I used it for about a year before the swap and it's been on the shelf for about 16-18 months since. Same cables so far, made sure same ends went into the corresponding slots.
 
The 700 is a seasonic s12 bronze, I know it's good because it was my previous psu before I swapped in the gigabyte p850gm. I used it for about a year before the swap and it's been on the shelf for about 16-18 months since. Same cables so far, made sure same ends went into the corresponding slots.

Oh no, that's very bad news. Modular PSU cables are not interchangeable. It's no wonder your problem has gotten worse; you never, ever do this unless you know for a fact that the pinouts on the modular side are the same. It's now more than likely 12V power has gone to places it shouldn't, which is usually an instant death sentence.

You're now in the "potentially swap every part in your build" stage or you'll need to bring it to a shop.
 
I don't get it. When I swapped psus, I unplugged only on the psu side. Replugged cable by cable to ensure positioning was identical, 24 pin in the 24 pin, pci-e/cpu in the pci-e/cpu, etc. The positions of the sockets were identical between the two, and except for the style labelling was the same, I assumed they would have the same output per socket since neither came with manuals. The cable positioning was the same between swaps. I thought positioning would be standard across brands and models
 
I don't get it. When I swapped psus, I unplugged only on the psu side. Replugged cable by cable to ensure positioning was identical, 24 pin in the 24 pin, pci-e/cpu in the pci-e/cpu, etc. The positions of the sockets were identical between the two, and except for the style labelling was the same, I assumed they would have the same output per socket since neither came with manuals. The cable positioning was the same between swaps. I thought positioning would be standard across brands and models

Modular power cables are only universal on the side that connects to the components. They are not universal on the side that connects to the PSU. Pinouts are different from manufacturer to manufacturer. Frequently pinouts are different in slightly different models from the same manufacturer.

Again, what this means is that there's a very good chance that you sent 12V power to somewhere 12V power should not be. And if this is the case, this is a salvage operation more than a repair. You'll need to test each part in a working system. This is a real mess to sort out, especially since you likely still have the original problem before possibly making a far worse one.
 
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Looks like I not working for a few days. Need to look for a shop I guess. Let you guys know what happens

Edit: apologies for the invective and thanks for the save/edit
 
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Here is an example. On the left side is the modular pinout of a PSU-side SATA connector in a Corsair PSU that uses Corsair Type 4 modular cables. On the right side is the modular pinout of of a PSU-side SATA connector in a SeaSonic Focus.

Untitled.png


(Yellow is +12V, red is +5V, orange is +3.3V, black is ground, and white is no wire).

If someone had a SATA modular cable connected to a hard drive in that Corsair PSU, unconnected the cable on the PSU side and connected it into the SeaSonic, very bad things happen to that hard drive.
 
Just got back from the shop.

Good News: Typing this out on my rig.

Better News: Nothing got fried.

Diagnosis was during the transfer of my tower from my table to my work area, the tower got jostled kinda hard somehow misaligning the heat sink and bending a few of the cpu pins. It took the tech a couple of hours to straighten things out. Everything works fine now.

I'm choosing to take this as a very expensive lesson in IT (the tech did tech me a couple of good ways to do better insulation and I got a couple of lessons here on how to properly handle psus in the future

Many thanks to ChumP and DSzymborski for putting up with my less than stellar approach to this issue. Again thanks!