The PC fails to power on, yet its USB ports remain operational.
The PC fails to power on, yet its USB ports remain operational.
Hi everyone,
I’m facing some problems with my 6-year-old PC that I’m struggling to identify. According to the title, recently the computer stopped turning on altogether. Even when I plug it in and switch it on, there’s no response from the motherboard. At first, I thought it might be a problem with the power supply or the motherboard, but I noticed I have power coming from the USB ports on both the case and the board.
Before sharing this issue, I’ve tried several troubleshooting steps:
- Used a different socket and power cable
- Performed a paperclip test on the PSU (it seems to work)
- Removed and reinserted the CMOS battery after waiting
- Booted without the GPU
- Disassembled and reassembled most parts, checking connections and loose cables
Still, the PC doesn’t show any life signs. No power surge or unusual event occurred, and the machine wasn’t moved.
Here’s a quick overview of my setup:
Intel i7 7700k
NZXT Kraken x53 AIO Liquid Cooling
Aorus GA-Z270X-Gaming 5
Vengeance 16GB RAM
GeForce MSI 1080
EVGA 750 80 plus gold
Anyone have any advice or insights? Thanks a lot!
USB receives power from a +5V supply. The CPU and GPU draw power from a +12V source. If the power supply doesn't deliver the +12V rail, the PC won't start, though USB ports will still receive energy.
What is the model or part number of the PSU? How recent is it, and was it purchased new or used/refurbished?
Thank you for your quick reply!
This makes complete sense. Using the USB device and the successful paperclip test helped focus on other potential faults, but you're correct—the +12V rail isn't definitively showing issues yet. Appreciate the advice!
It's an EVGA Supernova 750 G2, model 220-G2-0750. It should still be covered under warranty, so a replacement should be possible.
I have another functional PSU available soon, so I plan to swap them and check if that fixes the problem.
Thanks a lot! I'll update you once I see the outcome.
EVGA SuperNova G2 stands out as a top-tier model from EVGA, offering solid quality. However, issues can still arise, which is why a warranty exists. If problems persist, initiate an RMA and request a replacement. When testing with a second PSU, always use the power cables that came with it to avoid damaging your equipment.
Oh, thank you, you are a life saver! I honestly didn't know about this, I would have 100% re-used those already in place. As soon as I'll have a chance to try it, I'll let you know how it goes.
Thank you!
I verified by searching online and confirmed there are no safety concerns. Still, I attempted a switch and faced the same issue—no changes, and the other PSU was functioning until about an hour ago. Once connected, nothing happens except USB ports working, and turning it on seems ineffective. I’m leaning back to the dead motherboard theory again. Any suggestions or tests would be appreciated!