Hey everyone! I'm having a bit of a puzzling situation with my new PC build. I've been building computers for a while, but I'm no expert. I'm upgrading from an almost 8-year-old setup to a new motherboard, CPU, RAM, and power supply. The GPU is still decent, so I kept that.
So, I've got this new motherboard that has an 8-pin power slot and a 4-pin slot right next to it. After finishing the build last night, I hit a wall—nothing would power on at all. No fan spins, no BIOS screen, not even a sound from the PSU fan. I thought my PSU was dead!
This morning, I did a little testing (paperclip method) and found nothing worked. After further investigation, I discovered that my CPU power cable is the culprit. I have two CPU connectors on my PSU labeled CPU1 and CPU2. When I connect just the 8-pin cable to CPU1, everything works fine. But the moment I plug in the additional 4-pin to CPU2, the whole thing shuts down.
I've tried three different cables for that 4-pin and reset the CPU plugs, but the same issue persists. What could be causing this? Do I need a specific type of 4-pin connector, or is something else going on? I know the extra 4 pins are mainly for overclocking, but I'd like to have it plugged in for stability if possible. I'll share some pics in the comments for reference!
2 Answers
That sounds really strange. It seems like something with that extra CPU power connection is having issues, either the power supply, the cable, or the motherboard connector itself could be to blame. Unfortunately, without swapping in known good parts, it’s tough to diagnose. That said, your CPU shouldn’t need the extra 4-pin connector to run properly, so it might not be critical in your case.
From what you're describing, the 4-pin connector on your motherboard might be faulty or shorted somehow. Alternatively, check to see if anything metallic is touching the back of the motherboard, causing a short.
Good point, but I can’t see anything behind there. I’m using risers to keep it elevated, so it shouldn’t be touching anything. However, I still think the issue might be linked to the motherboard since it powers on perfectly with just the 8-pin.
I see what you're saying, but it really bugs me that I can't figure out the problem. I tried swapping the connectors and even used three different cables with no change. Should I test the power supply from my old PC to see if it might be the issue? If that works, at least I can rule out the power supply!