0

I decided to upgrade one of my systems. It was running fine, but the 10-year-old motherboard was underpowered. The power supply was a Corsair AX760, which had about one year of service. I left the PSU, cables, and case fans in place, pulled out the old motherboard, and replaced it with the same components that I used on another system:

  • MSI MAG Z790 Tomahawk motherboard (love these!)
  • Intel I7-13700K
  • Noctua NH-D15S CPU cooler
  • CORSAIR Vengeance DDR5 RAM 64 GB (2x32 GB) 6800MHz CL32 Intel XMP iCUE Compatible (CMK64GX5M2X6800C32)

I also reused the same video card, an MSI GeForce RTX 3060 Ventus 3X 12G OC GGDR6 PCI Express 4.0.

When I turned on the power, nothing happened. I used a PSU tester and found that the PSU provided no voltage. That was odd, it had worked well until then.

PSU tester

I purchased a CORSAIR RM1000X (the same PSU used in a similar system) and tested it before installing it. It worked. Still using the old PSU cables, I replaced the dead PSU with the RM1000X. Again, nothing happened when I turned on the computer. I tested the new PSU - it was now dead.

This seems like what would happen if an internal fuse or breaker shut down the PSU. However, there is no externally accessible fuse or breaker. Corsair does not offer support for their PSUs; they cite liability issues.

I ordered a replacement RM1000X. It is still in the box. I will:

  • Test the newest PSU before installing
  • Not use any of the old cabling
  • Unplug all components, including the CPU, from the motherboard before the smoke test

Can anyone suggest what the problem might be, or how to proceed without destroying a third PSU?

Might there be a problem with the motherboard? How could I test this without blowing up another PSU?

Improve this question
5
  • 2
    I cant tell you what's causing this, but i can tell you that cables for modular power supplies are not by default interchangeable. Check the pinout on the PSUs or better yet, use the correct ables that come with the new PSU. Ofcourse, wrong pinouts will blow your equipment, not your PSU; so that's not what happened. Just pointing out it was a bad idea to keep the old cables like that.
    – Silbee
    Commented Jun 22 at 10:57
  • Even modular power supply cables from the same manufacturer but different product line can be incompatible with one another. If the PSU is under warranty, issue an RMA, let the company diagnose the problem. Have you tried a different outlet?
    – Ramhound
    Commented Jun 22 at 14:48
  • I need an answer faster than however long an RMA process is likely to take. Never mind about the cable issue, I will use the cables that came with the newest PSU. Might there be a problem with the motherboard?
    – Mike Slinn
    Commented Jun 22 at 17:06
  • @MikeSlinn - If the problem was a cable incompatibility problem there is a chance damage was done but impossible to confirm
    – Ramhound
    Commented Jun 22 at 18:05
  • Know anything about internal fuses or breakers in a PSU?
    – Mike Slinn
    Commented Jun 22 at 23:35

0

Reset to default

You must log in to answer this question.

Browse other questions tagged .