Does a circuit breaker trip when connecting a new PC?
Does a circuit breaker trip when connecting a new PC?
I recently acquired a new PC equipped with these specifications:
CPU: AMD Ryzen 7 9800X3D
CPU Cooler: NZXT Kraken Elite 360 RGB (2024) – 360mm AIO
Fans swapped for Lian Li UNI Fan SL Infinity 120mm (3-pack, Fluid Dynamic Bearing)
Motherboard: Gigabyte B850 AORUS ELITE WIFI7
Power Supply: Asus ROG THOR P2 Gaming 850W, 80+ Platinum Certified, Fully Modular ATX
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
Accessories: Power/RGB Kit – Lian Li Strimer Plus V2 (Wireless RGB with RF Controller)
Including: Dual 16-Pin GPU Strimers, 24-Pin Motherboard Strimer, 2×3-Pack UNI Fan SL Infinity 120mm (Standard + Reverse), 1×3-Pack Reverse, and 1 Single Fan Unit
My friend assembled and tested the PC prior to shipping. It operated smoothly for two hours at his location. However, upon installation in my space, it frequently tripped the circuit breaker—sometimes within 10–30 minutes, occasionally immediately—even during light activities such as streaming YouTube or logging in.
I reside in a small town where PC support is scarce. Local repair shops charge around $190 just for diagnostics.
Temperatures were monitored with HWMonitor. Most components functioned normally, but the CPU cooler maintained around 80°C, which appears elevated and could stem from 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 own the PC, monitor, and charger.
I contacted my home warranty provider to dispatch a technician.
Tech 1: Suspected the 20A AFCI/GFCI breaker was defective—possibly overheated (Texas climate). Inspected wiring, grounding, outlets, and found no faults. Suggested replacing the breaker but couldn’t complete the work as he departed for vacation.
Tech 2: Upon arrival, he tested and replaced the outlet; issue persisted. Requested wattage specs. Clarified PSU is 850W, monitor 60W. Explained the PC likely draws ~750W under load, not full 850W. Tested in living room—no breaker trip or shutdown. Mentioned the first technician’s theory about the breaker. He said he lacked time and would return, but never did. He submitted a claim that my system was overloading the circuit.
Tech 3 (Independent Electrician): Opened the breaker, initially detected 0.20V then 120V after reset. Also recommended replacing the breaker. Estimated cost $500.
Additional Online Insights and Theories:
- Faulty PSU causing inrush current and triggering AFCI protection
- Breaker failure likely responsible
- Consider using a UPS to smooth startup spikes
- Concern about PSU quality—possibly damaged during shipping, risking further damage
- Alternative advice: Verify outlet condition with Klein Tools Receptacle; confirmed correct.
I also performed a self-test on the outlet using Klein tools and received confirmation.
We checked the PC in the living room, and it didn’t cause the breaker to trip or shut down automatically.
Probably not a power supply issue—consider testing other areas or circuits.
Are other high-power devices like small heaters, vacuums, dryers, AC units, or tools affecting the breaker?
The Klein tester confirms the wiring is correct, so the problem likely lies elsewhere.
Technicians 1 and 2 probably have an interest in confirming there’s nothing wrong to avoid insurance costs.
Both should have identified the issue without much difficulty.
Technician 3 also focused on the breaker; the report matches what we expect.
Electrical repairs can be costly, even for simple tasks.
Last electrician: think about the extra charges you might face—ask questions about the necessity and reasoning behind fixes.
You’re at the mercy of local rates; seek a licensed professional with good references.
Talk to people around you—family, friends, coworkers—especially those who’ve done recent electrical work.
They might help negotiate a better price and ensure you get proper parts and warranty.
I’ve checked the PC on various circuits and in different rooms—sometimes it shuts the breaker right away, other times it takes a while. I left it on for a longer period during my next test. I was worried initially about leaving it on too long, so I turned it off after five minutes.
Have you checked if other high-power devices (such as a space heater, vacuum cleaner, hair dryer, window AC, or power tools) cause the same circuit to trip?
In my experience, no other appliances trigger the breaker—only the PC does. This has never occurred before; the breaker only activates when the PC is connected. I’ve tried other devices and they all function properly.
The Klein tool is a simple receptacle tester that lights up to show whether the wiring is correct. It currently indicates everything is fine. I tested several outlets in my room, and all are showing proper readings.
The first technician mentioned he would attempt to replace the breaker switch under the home warranty if time allowed, but he didn’t follow through. They assigned a different technician, which I found unprofessional. The appointment was set for 10:00 AM, yet he arrived at 4:00 PM. Around 4:30 PM, he left to install a fan for another customer and said he needed to go elsewhere before returning. He told me to purchase a new outlet so he could replace it—something I found unusual since the previous technician never asked for any parts. The new outlet was cheap, so I bought it. He returned about 40 minutes later, swapped the outlet, and before leaving, I asked to test it. The PC immediately tripped the breaker again. He claimed he didn’t have time to investigate and would return later, but he never did.
The third technician initially offered to replace the breaker switch to see if that would resolve the problem, but instead gave me a quote for repairs. When I inquired about costs, he said it would depend on what needed fixing or replacing, and he wouldn’t know until he encountered the issue firsthand.
I’ve spoken to friends, family, and coworkers, and several electricians quoted $150–$200 per hour, with additional fees when the problem was identified. Many people on Reddit reported that replacing their power supply unit resolved the issue, so I might consider that option since it’s currently the most affordable. It has been nearly two months since I got the PC, and the breaker only trips when the PC is turned on.
Very useful and I reviewed the discussion so far.
I just noticed: what is the make and model of the power supply? The wattage (recorded as 850)? Is it new, used, or refurbished? If needed, ask a friend for details.
I was going to ask the same question as Ralston18 regarding the PSU.
It's tough to be certain without being there and verifying personally, but I lean toward thinking it's the PSU or possibly another component in the PC, maybe an intermittent issue. The 80ºC idle temperature is quite high.
The fastest way to determine this would be to swap out the PSU.
But the $175 labor cost seems extremely unfair, as do the other charges from electricians. I sometimes feel lucky to live in a third-world country.
The PSU is an Asus ROG THOR P2 Gaming 850 W, Platinum Certified, fully modular ATX power supply. I purchased it from Amazon new and delivered it to his place during a sale. I’m not sure if that affects anything. The work took about an hour, but I’m curious—could the CPU temperature be due to the thermal paste? Sorry, this is my first PC and I’m still learning about them.
I have a PC next to a microwave, coffee maker, and toaster oven. When any three devices run at the same time I trigger a 15A breaker trip. Breakers activate when the load exceeds a certain limit. If they fail, faulty ones can cause the trip. The issue occurs on multiple outlets on the same circuit, suggesting a problem with the breaker. Replacing breakers is straightforward and affordable. A GFCI breaker costs around $60 but doesn’t require special licensing to install. Simply purchase the same model, switch off the power, and replace it (snap-in). This would be my initial action.
Even the most affordable thermal paste won't raise the idle temperature as much if applied correctly and the cooler is properly seated, ensuring solid thermal connection with the CPU. Regarding the power supply, it might be a unit that was sent back due to the issue you're facing.
You should notice how the device operates. It will also identify overload situations. It’s likely you’ll see some useful figures before the circuit breaker trips. This can indicate whether the computer is consuming excessive power. When it draws more than 850 watts, it points to a serious problem.
These images show the CPU and the outlet. If the thermal paste isn’t the issue, what other factors could be leading to the CPU overheating? Also, thank you for suggesting that tool—I’m ready to place the order now.
I’m okay with spending for the breaker switch. I think a model around $75 would work, as it includes AFCI and GFCI protection. My main worry is hiring the third technician to replace it, but only if the problem is the power supply unit. Since my breaker doesn’t have a main switch to cut power, it’s unclear exactly where the issue lies.
Should I call him back and ask about other devices connected to the same circuit in my room?