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PC won't boot with 8-pin CPU power but 4-pin works?

SAMURONIN

New Member
Joined
Oct 6, 2024
Messages
6 (0.03/day)
Hello, I'm pretty new to PC building and I have this issue where my PC won't boot when I connect the 8-pin CPU power

Tried a whole bunch of things (resetting CMOS, tried an older CPU, reseating CPU, tested each DIMM slots, changing GPUs, switching out PSU, etc...) and had the idea to just use 4-pins instead of 8 pins and it booted. I thought it might've been a faulty PSU so I replaced it with ST60F-ES Silverstone 600w 80+ which I know still works because I've used it before but for some reason 4-pins & 8-pins won't work(?). I switched back to the the original PSU (cooler master masterwatt650 Bronze) and it works but only with 4-pins attached

Any idea what is causing this?

Test Setup:
Ryzen 5 3600
8GB DDR4 3200 CL16
RTX 3070 Vision OC
Asus Prime B550m-A
Kingston NV2 1TB
Cooler master MasterWatt650 80+ Bronze

IMG-20241005-WA0072.jpeg
 
Last edited:
Are you 100% certain that any/all of the PSU cables in use are correctly matched to the PSU they came with at any given moment? Do not under any circumstances share cables between different PSU manufacturers (or, in some cases, even different PSU models from the same manufacturer).
 
Are you 100% certain that any/all of the PSU cables in use are correctly matched to the PSU they came with at any given moment? Do not under any circumstances share cables between different PSU manufacturers (or, in some cases, even different PSU models from the same manufacturer).
I'm 100% certain the cables all belong to the original PSU, I usually keep the extra cables in the same box it came with so I don't lose them. Plus, the Cooler master PSU I'm using is semi-modular with the CPU cable already attached to the psu while the Silverstone PSU I was testing it out with is non-modular
 
have you double check? the pin layout? it's weird if you got the right cable but won't post
 
Just an update, I finally got it to post with 8-pins

I was playing around with the bios settings while using 4-pins & the PC was able boot afterwards with 8

Don't exactly know which of these settings helped or if they even helped at all but here's what I did

1. Turned on ReBAR
2. Set PCIEX16 Mode to Gen 4
3. Set M.2_1 Link Mode to Gen 4
4. Disable USB power delivery in Soft Off State
5. LED Light when system in working state set to Aura Only

I also used two separate GPU PCIE cables instead of 1
 
Clear cmos and see if you can boot with factory defaults
 
When using only one 4 pin CPU connector it should be placed in the one closest to the CPU socket, not the one used as seen in the picture.
 
CPU won't power up when I connect the 4-pins closer to the CPU, only the 4-pins on the left works but no worries I fixed it already
 
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