Question Computer Won't Boot Unless I Switch Power Outlets

[Zennistrad]

I'm having an extremely bizarre issue with my PC: after getting both the motherboard and power supply unit replaced, I'm unable to get my desktop PC to boot properly - I get a "DRAM" and "CPU" light on the motherboard and the PC does not connect properly to the monitor.

However, when I took my PC to the local repair shop, they've been completely unable to replicate the issue at all. They've been able to boot the PC up with no problem.

But when I plug my PC in at my apartment, the issue persists. The only fixes I've found so far are switching power outlets to a different power strip, and switching the PSU in the back off, leaving it for ten minutes, and turning it back on. Both of these fixes will occasionally solve the problem but it's very inconsistent.

I have genuinely no idea what the problem could be. The only differences I can think of between what I'm doing and what the repair shop did are a) I'm using a different power outlet and b) I have a different power cable/monitor/keyboard than them.

For reference, this my current setup for the motherboard and CPU, but I doubt it's relevant to the issue at all:

CPU: AMD Ryzen 5 5600G

Motherboard: ASRock B550M-C

GPU: NVIDIA GEForce RTX 3060

And I've also generally noticed that the boot problem most often happens after playing a game installed to my HDD for several hours, though it's also happened even when I never touch the files on the HDD at all.

I'm at a complete loss for what the problem could be, any advice would be appreciated at this point and I've so far not been able to get much help anywhere.

 

[rgd1101]

brand and model of the psu?

 

[geofelt]

Test your outlet for proper grounding and polarity.
Use a simple $10 tester like this:
https://www.homedepot.com/pep/Recep...24-71700000118279182--&gad_source=1&gclsrc=ds

 

[stonecarver]

The only fixes I've found so far are switching power outlets to a different power strip,

I agree with geofelt to test the outlet.

Another thing to try is not use the power strip. Our power supplies are switching devices and every now and than we get a power strip + computer that just hates each other.

After you have a chance to post make and model of power supply like

rgd1101​

said it will help us to know if it could actually be the power supply.

 

[Zennistrad]

Sorry for the delayed reply. I was busy the past several days with other things, but I've found the power supply info. From what I can tell, it's an EVGA 650 B5:

https://www.evga.com/products/product.aspx?pn=220-B5-0650-V1

After some fiddling, I've also finally gotten the PC to boot again. Not sure what changed, but I did wipe off some of the dust that had gathered on the power cord before plugging it back in.

 

[Zennistrad]

Update: the computer is once again having boot issues. I've tried cleaning the power cord, as well as replacing it with a new one, but it's still having trouble. The power light turns on but it won't start beyond that, and I still see the DRAM and CPU warning lights.

Any advice on what to do next?

 

[LinuxDevice]

Is your power outlet perhaps too far out of spec and delivering low voltage? I don't recommend getting yourself electrocuted, but if you have a meter and can measure the voltage at the socket with and without the computer on it might give a hint. Someone mentioned a socket tester earlier, and that can reveal issues. A bad power strip would do the same, but a good power strip inheriting from a bad outlet would have the same effect.

 

[Zennistrad]

Is your power outlet perhaps too far out of spec and delivering low voltage? I don't recommend getting yourself electrocuted, but if you have a meter and can measure the voltage at the socket with and without the computer on it might give a hint. Someone mentioned a socket tester earlier, and that can reveal issues. A bad power strip would do the same, but a good power strip inheriting from a bad outlet would have the same effect.

It's definitely not the power strip - same issue happens on wall power directly. I do suspect there might be a problem with wall power though because this apartment building has sometimes struggled with power, since it's very old and has had occasional 1-2 minute blackouts with the road work being done outside.

The power in my apartment room works fine with every electrical appliance I have except for the PC though, which is odd. Even the refrigerator, which I would think would use more power.

 

[stonecarver]

since it's very old and has had occasional 1-2 minute blackouts with the road work being done outside.

The power in my apartment room works fine with every electrical appliance I have except for the PC though, which is odd. Even the refrigerator, which I would think would use more power.

That being said it's hard to nail down a solution as outside factors are at play. Although the power supply is robust it's more sensitive and gets finicky.

I would get a watt meter that can read the walls sockets volts as well.

https://www.amazon.com/P3-P4400-Ele...lpcontext&ref_=fplfs&smid=A3MIP8D2FH3WRX&th=1

 

[Zennistrad]

That being said it's hard to nail down a solution as outside factors are at play. Although the power supply is robust it's more sensitive and gets finicky.

I would get a watt meter that can read the walls sockets volts as well.

https://www.amazon.com/P3-P4400-Ele...lpcontext&ref_=fplfs&smid=A3MIP8D2FH3WRX&th=1

I can probably grab one of those, yeah.

Out of curiosity, what would I be looking for in terms of the voltage that the wall socket should have?

 

[Zennistrad]

That being said it's hard to nail down a solution as outside factors are at play. Although the power supply is robust it's more sensitive and gets finicky.

I would get a watt meter that can read the walls sockets volts as well.

https://www.amazon.com/P3-P4400-Ele...lpcontext&ref_=fplfs&smid=A3MIP8D2FH3WRX&th=1

One thing I should also note here:

When the repair shop tried to replicate my problem, they noted that the "DRAM" and "CPU" lights on the motherboard briefly switched on, but then shut off and the PC booted normally every time they tested it.

These are the same lights that turn on whenever my PC fails to boot altogether.

I'm not sure if that makes any difference, but that's also something that could help identify the issue. What do you think of that?

 

[stonecarver]

These are the same lights that turn on whenever my PC fails to boot altogether.

Do they STAY on when it won't boot. If they do than that should say something.

Again we don't know if it's dirty power from the wall socket as like you said it worked fine at the repair shop.

Can you just have a power supply that just does not play nice with where your plugging it in at home.

I have built many computers that worked just fine when I built them only to fail at the clients house. No boot issues.

Bring it back to the shop flip out the power supply and it fixed the issue.

Weird thing the power supply that misbehaved at the clients house always work in other machines.

 

[LinuxDevice]

It's definitely not the power strip - same issue happens on wall power directly. I do suspect there might be a problem with wall power though because this apartment building has sometimes struggled with power, since it's very old and has had occasional 1-2 minute blackouts with the road work being done outside.

The power in my apartment room works fine with every electrical appliance I have except for the PC though, which is odd. Even the refrigerator, which I would think would use more power.

I'm thinking of the wall itself. If the wall socket is an issue, then only a brownout-protecting UPS would help that. Power outlets are seldom considered suspect, but the number of times that there is some issue with the wiring in the wall itself is far higher than most people would suspect. Issues range from simply being lower than spec voltage to incorrect grounding (such grounding may not show up in most use, but on hardware that depends on correct grounding it can toggle shutoff).

EDIT: Think "specs", not "it works for other things". Do you have a way to test the voltage of the socket when in operation?

 

[Zennistrad]

Do they STAY on when it won't boot. If they do than that should say something.

They do, yeah.

I am definitely thinking it's an issue with the wall power itself, as @LinuxDevice mentioned just a bit ago, but I'm not going to be able to properly test with a voltmeter until I'm able to pick one up. It might take until next week to ship to me (I live a fair bit out of the way from the nearest hardware store and don't currently own a car) so I'll see if I can figure something out with that in a bit.

 

[LinuxDevice]

Don't forget what @geofelt mentioned in #3, that there is a testing device. The testing device can suggest if grounding is correct, but you'd still want to know the socket is not in a brown-out condition/undervoltage.

 

[LinuxDevice]

It's definitely not the power strip - same issue happens on wall power directly. I do suspect there might be a problem with wall power though because this apartment building has sometimes struggled with power, since it's very old and has had occasional 1-2 minute blackouts with the road work being done outside.

The power in my apartment room works fine with every electrical appliance I have except for the PC though, which is odd. Even the refrigerator, which I would think would use more power.

Btw, if your apartment does have an issue, then a higher end (but still not super expensive) UPS which protects from brown-outs would solve this (along with protecting the hardware).

 

[Zennistrad]

Alright, so I finally managed to get myself both a receptacle tester and a proper voltmeter.

The receptacle tester seems to indicate that it's working fine, with the center and left lights lit up, which the diagram indicates means "correct"

I also bought the Wattmeter from the Amazon link below


https://www.amazon.com/P3-P4400-Ele...lpcontext&ref_=fplfs&smid=A3MIP8D2FH3WRX&th=1

and this is what it's giving me:

122.20 Volts

0.48 Amp

56.4 - 56.6 Watts

60 Hz

I'm not really an electricity guy by any means so I'm not sure, but the Amperage here seems way too low - can anyone here confirm?

The power supply specs say that this is the AC input:

100-240V~, 10-5A, 60/50Hz

 

[Ralston18]

I have the same Kill-A-Watt meter.

Placed between the wall outlet and the UPS serving computer and monitor.

Voltage shown as 119.5 volts. Varies a bit....

Current shown as 0.48 amps but may go a bit higher from time to time.

= = = =

Multiply volts x amps to get wattage.

 

[Zennistrad]

I have the same Kill-A-Watt meter.

Placed between the wall outlet and the UPS serving computer and monitor.

Voltage shown as 119.5 volts. Varies a bit....

Current shown as 0.48 amps but may go a bit higher from time to time.

= = = =

Multiply volts x amps to get wattage.

Yup, that matches what I'm getting. I'm thinking at this point the issue is the wattage. The sources I find online for my PC specs recommend a wattage more than twice of what I'm getting for all of my current power outlets - even the fridge maxes out at around 80 watts. I'm definitely gonna have to see if I can get an electrician to look at it.

 

[DaleH]

Yup, that matches what I'm getting. I'm thinking at this point the issue is the wattage. The sources I find online for my PC specs recommend a wattage more than twice of what I'm getting for all of my current power outlets - even the fridge maxes out at around 80 watts. I'm definitely gonna have to see if I can get an electrician to look at it.

I'm not sure what you are saying. The amount of power drawn by a device is not determined by the source, but by the load. P(power)= I(squared) X R. Where P is the power drawn by the device (computer) and I is the current drawn from the source, and R is the resistance in ohms that is the load (your PC).
It's possible that there is a high resistance in the electrical lines going to the outlets. In that case any current drawn by your computer (or any device) would cause the output voltage present at the outlet to be lower because of a voltage drop across the internal resistance of the house wiring. One can determine if that is a problem by measuring the AC voltage at the outlet with and without the pc connected. It should be unchanging if the internal wiring of your house is not the problem. Your voltmeter can be used to test it. Not sure if I've been any help; I'm not a PC expert, but I am on basic electricity and electronics. Please reply if I can be of further help. I'm sure we can pinpoint the source of the problem.

 

[Zennistrad]

I'm not sure what you are saying. The amount of power drawn by a device is not determined by the source, but by the load. P(power)= I(squared) X R. Where P is the power drawn by the device (computer) and I is the current drawn from the source, and R is the resistance in ohms that is the load (your PC).
It's possible that there is a high resistance in the electrical lines going to the outlets. In that case any current drawn by your computer (or any device) would cause the output voltage present at the outlet to be lower because of a voltage drop across the internal resistance of the house wiring. One can determine if that is a problem by measuring the AC voltage at the outlet with and without the pc connected. It should be unchanging if the internal wiring of your house is not the problem. Your voltmeter can be used to test it. Not sure if I've been any help; I'm not a PC expert, but I am on basic electricity and electronics. Please reply if I can be of further help. I'm sure we can pinpoint the source of the problem.

Most sources I've seen when looking into suggests that, at minimum, a desktop PC should be using around 300W of power, even just an office desktop without a fancy GPU. That's not even close to what I'm getting here when I try to turn it on.

When the voltmeter isn't plugged into anything else, it hovers at around 122 volts, but occasionally it seems to increase to 122.5V

 

[Zennistrad]

Alright, it turns out I was misunderstanding how the electricity works - entirely my bad, I'm entirely out of my depth when it comes to that topic.

But I have figured out how to fix the issue. Turns out, unplugging the Air Conditioning from the room's power, then disconnecting and connecting all the computer cables to the wall outlet, solved it completely. My PC's been booting up consistently for three days now, and if I had to guess, something about the excess power usage of the AC has been messing it up somewhere.

 

[stonecarver]

But I have figured out how to fix the issue. Turns out, unplugging the Air Conditioning from the room's power, then disconnecting and connecting all the computer cables to the wall outlet, solved it completely.

I'm glad you have it figured out. Computers and AC units on the same circuit not a happy mix.

 

[Zennistrad]

Welp, that didn't work long.

After a lengthy gaming session on Sunday night - played from a game I had installed to my HDD - the computer's now having boot issues again. I've noticed that while I was playing, the fan was running particularly loudly, but otherwise nothing out of the ordinary until the boot issue started again.

While booting, I noticed that it briefly showed the pre-boot screen on the monitor before abruptly switching off, but after that it gave me nothing.

I called another computer place and they told me the issue might just be with the motherboard, it's possible that the computer place that replaced it installed it incorrectly. The only things I can think of that might also be the issue are the RAM and CPU but I have no way of knowing right now.

 

[Zennistrad]

Okay, so.

I just got myself a UPS - an APC Back-UPS Pro BN 1500VA.

APC Back-UPS Pro, 1500VA, Tower, 120V, 10 NEMA 5-15R outlets, LCD, 1 USB Type C + 1 USB Type A ports - BN1500M2 | APC USA

BN1500M2 - APC Back-UPS Pro, 1500VA, Tower, 120V, 10 NEMA 5-15R outlets, LCD, 1 USB Type C + 1 USB Type A ports | APC USA

www.apc.com

I tested my desktop on the UPS using both battery power and the standard surge protector. Both of them didn't work, which suggests that whatever issue my PC is having isn't the power after all.

More strangely, when both my monitor and my PC were connected to the UPS, the monitor also seemed to break after several tests. The model is an Acer s231HL

https://www.newegg.com/acer-s231hlbid-23/p/N82E16824009255

Now, whenever it's plugged in, the blue "on" light on the power button turns on, but the screen never connects, and I can't turn the monitor "off" - the light remains blue no matter how many times I press the power button to switch it off.

I've tested this with my laptop; this is purely an issue with the monitor now. The monitor does not connect to any device using any HDMI cable I have.

So, unless there's some really, really, really unfortunate timing here, something about my PC somehow broke my monitor too.

Any idea what's going on here?