Question Circuit Breaker trips when using new PC ?

[Nguyen2526]

I recently got a new PC with the following specs:

• CPU: AMD Ryzen 7 9800X3D
• CPU Cooler: NZXT Kraken Elite 360 RGB (2024) – 360mm AIO
• Fans replaced with Lian Li UNI Fan SL Infinity 120mm (3-pack, Fluid Dynamic Bearing)
• Motherboard: Gigabyte B850 AORUS ELITE WIFI7
• PSU is Asus ROG THOR P2 Gaming 850 W 80+ Platinum Certified Fully Modular ATX Power Supply
• RAM: Corsair Vengeance RGB DDR5-6000 CL36 – 64GB (4×16GB)
• GPU: Zotac GAMING AMP Extreme INFINITY GeForce RTX 5070 Ti
• Storage: WD_BLACK SN850X 1TB NVMe SSD (Model: WDS100T2X0E)
• Case: Lian Li O11D EVO RGB
• Power/RGB Accessories:
  • Lian Li Strimer Plus V2 (Wireless RGB w/ RF Controller):
    • 24-Pin Motherboard Strimer
    • Dual 16-Pin GPU Strimer
  • Lian Li UNI Fan SL Infinity 120mm (Standard + Reverse):
    • 2× 3-Packs (Standard)
    • 1× 3-Pack (Reverse)
    • 1× Single Fan Unit

My friend built and tested the PC before shipping it to me. It ran perfectly for two hours at his place. However, after setting it up in my room, it began tripping the circuit breaker—sometimes within 10–30 minutes, other times immediately—even during light tasks like watching YouTube or logging in.
I live in a small town where PC support is limited.
Local repair services charge around $190 just for diagnostics.
I checked the temps using HWMonitor. Most components are fine, but the CPU cooler idles at around 80°C, which seems high and might be due to a thermal paste issue (possibly an air bubble).
My brother's room and my room share the same circuit breaker. He only has a TV and a phone charger plugged in. I have the PC, monitor, and a charger.
I called my home warranty company to send someone out.



Technician 1:
Suspected the 20A AFCI/GFCI breaker was faulty—possibly heat-damaged (I’m in Texas).
Tested the wiring, ground, outlets, and for loose wires—no issues found. Recommended replacing the breaker, but couldn’t finish the job as he was leaving for vacation.



Technician 2:
When he came out, he tested and replaced the outlet (the issue persisted). Asked for wattage details. I told him the PSU is 850W and the monitor is 60W. I clarified that the PC likely only draws about 750W under load, not the full 850W. We tested the PC in the living room, and it didn’t trip the breaker or shut itself off. I mentioned the first tech’s theory about the breaker. He said he didn’t have time to check that day and would have to return. Which he never did he submitted a report claiming my system was overloading the circuit.
The warranty company denied the claim, saying they don’t cover overloads or equipment upgrades.
I tried to appeal with the third tech’s diagnosis, but they still denied it.



Technician 3 (Independent Electrician):
He opened and tested the breaker. Initially got 0.20V, then 120V after a reset. Also recommended replacing the breaker. Quoted $500 for the job.



I also had one last technician come out to be sure and he said the breaker is perfectly fine nothing wrong with it and it could be damaged wires in either mine or brother room he’s charging $280 for one bedroom just to check outlets and light switches if he finds anything he will charge extra to fix it.



Online Suggestions and Theories:

• Faulty PSU
• Inrush current triggering a sensitive AFCI breaker
• Breaker is bad and needs to be replaced
• Use a UPS to buffer startup spikes

I’m worried that the psu could be faulty or got damaged during shipment and could damage other components. I bought the psu off of amazon ship&sold by Amazon
Someone offered to replace the PSU for $175 (labor only), but I’d still need to purchase a new PSU—I’m open to recommendations.
Any advice or insights would be greatly appreciated. I also tested the outlet myself with klein tools receptacle. Result: Correct.

 

[Nguyen2526]

I couldn't help smiling when I read this.

I don't know what he expects will happen if you buy a "standard" surge protector, but I doubt it'll have much (if any) effect on the initial current surge which flows into an ATX PSU.

Normal domestic surge arrestors contain little more than an MOV (Metal Oxide Varistor) which only protects against voltage spikes. They're completely useless protecting against current spikes,

This video shows what's inside a Belkin plug adapter designed for UK mains.

View: https://www.youtube.com/watch?v=EBFFBSZY17U


The MOV is the blue disc. Check out most US surge strips costing less than $40 and you'll probably find nothing more than one or two MOVs.

What you need is someting which combines MOVs to limit voltage spikes plus inductors (coils) to limit inrush current spikes. Best of both worlds, but significantly more expensive.

You might find this Isorbar4Ultra on your local Amazon site. Quite obviously it's expensive. It contains far more components.

https://www.amazon.ca/Tripp-Lite-ISOBAR4ULTRA-Isobar-Protector/dp/B0000513O4

If you buy a cheap surge arrestor, don't blame me if your computer still trips out your breaker.

I just hope the guy recommended some specific (high quality) surge arrestors with built in current limiting, as well as the more common voltage limiting.

A good surge arrestor might cost the same as an ATX PSU, but it's probably cheaper than calling out an electrician and paying them to change breakers.

I’ll just order the one you recommended then

Tripp Lite ISOBAR4ULTRA Isobar 4-Outlet​

 

[Misgar]

I’ll just order the one you recommended then

Excellent. Let us know if it fixes your breaker problem.

 

[thx1138v2]

"This is what I have my brother and I share #4"
Keep in mind that breakers only protect the wiring. So if you are both pulling current from the same breaker that is most likely he problem. Get an electrician to install another breaker so each breaker pulls its current from a separate leg of of the distribution panel.

 

[Nguyen2526]

"This is what I have my brother and I share #4"
Keep in mind that breakers only protect the wiring. So if you are both pulling current from the same breaker that is most likely he problem. Get an electrician to install another breaker so each breaker pulls its current from a separate leg of of the distribution panel.

I thought adding another breaker would be 1k+ depending

 

[Misgar]

I thought adding another breaker would be 1k+ depending

I don't know about you, but where I live, an MCB (miniature circuit breaker) costs the equivalent of US $5, leaving $995 for the electrician to install it.

I suggest waiting to see if the Tripp Lite Isobar4Ultra fixes the problem, before adding more breakers.

 

[Nguyen2526]

Hey everyone! My PC is finally fixed and stays on now 😀

Only issue is CPU temps—before the PSU replacement it was around 80°C in games, but after the guy replaced the PSU and reapplied thermal paste, it now hits 90–97°C.

I changed the battery settings to 90%, and it stays at 56°C idle, but jumps to 90–95°C when gaming (like Valorant). Also, the fans ramp up loud on startup.

Do you guys think maybe the guy applied too much thermal paste or possibly the cpu pump?

 

[artk2219]

Hey everyone! My PC is finally fixed and stays on now 😀

Only issue is CPU temps—before the PSU replacement it was around 80°C in games, but after the guy replaced the PSU and reapplied thermal paste, it now hits 90–97°C.

I changed the battery settings to 90%, and it stays at 56°C idle, but jumps to 90–95°C when gaming (like Valorant). Also, the fans ramp up loud on startup.

Do you guys think maybe the guy applied too much thermal paste or possibly the cpu pump?

I would check the mounting to make sure theres enough mounting pressure, check to make sure the pump is plugged into the right fan header on the motherboard, and check the fan curve in the bios. If everything is setup correctly, you may have a bad pump, in which case, replace it. Personally i would go with a decent air cooler and never have that problem again, thats a personal call though.

 

[Nguyen2526]

I would check the mounting to make sure theres enough mounting pressure, check to make sure the pump is plugged into the right fan header on the motherboard, and check the fan curve in the bios. If everything is setup correctly, you may have a bad pump, in which case, replace it. Personally i would go with a decent air cooler and never have that problem again, thats a personal call though.

Should I try to rma my cpu cooler?

 

[artk2219]

Should I try to rma my cpu cooler?

Have you checked everything else first? Whether the plastic cover was removed from the cold plate, that there is enough thermal paste to cover the CPU, that there is enough mounting pressure to assure good thermal transfer, that the pump is plugged into the correct header, and that the fan settings are good in the bios?

 

[bill001g]

It would be very strange that the cooler just happened to go bad when a power supply was replaced. For most pc you can replace the power supply without touching the cooling. It is a lot of extra work to remove the cooler from the CPU and then reapply it so nobody would do that unless you had some strange case where there was no other way to replace the power supply.

I really try to talk anyone thinking about AIO to use air coolers instead. AIO is so hard to troubleshoot and modern air coolers will easily cool pretty much any cpu unless you are overclocking.

There is not a lot you can try. Remove and carefully repaste the cpu and remount the cooler. I guess ensure the power cable to the pump did not get unplugged from the motherboard. Normally you get a warning if the the motherboard does not detect the connection.

 

[Nguyen2526]

The plastic cover has been removed, and I’m pretty sure the thermal paste is making contact with the CPU. The guy who reapplied it used a type of paste that has a marking or circle on the tube that tells him when he’s applied enough, so I’m not sure if he may have used too much.

Perhaps he might not have applied enough pressure when reinstalling the cooler. Is there a way to check that? Should I try tightening the screws a bit more?

The fans are working—I changed the settings to speed them up and I could hear them running. I also touched the tubes and felt that cooling is happening. He had removed the CPU cooler earlier because there was very little thermal paste applied originally.

https://imgur.com/a/o4nzkqT

View: https://imgur.com/a/o4nzkqT

I’m going to try to reapply it and see how it goes

 

[bill001g]

Too much is always better than not enough. It pretty much just makes a mess if you use too much.

Most modern coolers you want to tighten the screws until they stop. You do not want to use any real force. Most are designed that when you hit this point the metal brackets on the cooler are tight against the standoffs. Cranking down more on the screws will not really do any thing other than maybe break the screws. The cooler can not go down any father and also can not apply any more pressure to the cpu chip.

Although very tedious the best way to ensure good coverage of the cpu is to spread it manually yourself. The layer of paste is extremely thin. It is meant to fix imperfection in the cpu lid and the cooler. These imperfections are so small you can't even see them. depending on the brand of paste you can actually see the marking though the paste it is applied that thin.

 

[Nguyen2526]

Hey guys I finally changed the thermal paste and fixed some of the wirings and it works perfectly now! I think the psu was the issue thank you again everyone that helped me through this.