New PSU causes the PC to power on for just one second.
New PSU causes the PC to power on for just one second.
Hi everyone, here’s what I set up for my nephew:
I assembled a system using some spare components and new parts. The setup includes an Asrock A320M-HDV, a Ryzen 5 1500X, two 8GB Kingston DDR4 2400 modules, a 500GB WD Green M.2 NVME SSD, a GT 9600 512MB GPU (planned to replace with a GTX 1060 6GB), a Seasonic M12 II EVO 620W PSU (intended replacement but not done yet), a Silverstone Fara 312Z case, and other basic peripherals.
During installation, I tested the system extensively—running OS, Office, AV software, and various benchmarks for over three hours. Everything functioned properly.
Today, I replaced the old Seasonic PSU with a new Corsair RM650e. However, when I press the power button, the system powers on for just one second before shutting down immediately—no beep, no sound, nothing at all.
I tried many things: checking bare components, testing GPU in and out, using only one RAM stick, etc. The result remained consistent—just a brief startup and then an immediate shutdown.
After removing the new Corsair PSU and cables, I reinstalled the old one with its original cables, and the system worked fine. Then I rebuilt everything again, connecting fans, lighting, both RAM sticks, and pressing the power button—still booted without issues using the old PSU.
For confirmation, I’m considering returning the Corsair RM650e since it seems faulty. Any thoughts or advice would be appreciated!
I only used the cables that came with the new PSU.
Avoid mixing cables from various PSUs.
It seems you probably overlooked updating some older modular cables to the latest ones from the new power supply. This might be leading to issues. Make sure all your cables are up to date. Modular PSU cables don't work well with different power supply models. Incorrect cables can harm or destroy connected hardware.
I've been working on PC repairs and builds for more than 30 years as a paid job. I never mixed any cables, not even accidentally. There were just four cables—24-pin CPU EPS, PCIe, SATA, and one for the RGB controller—which I removed when the issue began. In the end, there were only three cables left.
New item, still in sealed packaging. I reviewed multiple videos and the Corsair site to ensure nothing was missing or incorrect. Everything appears correct.
I'm considering purchasing a new multimiter because my current one has been unreliable recently.
Since I own a Gigabyte B450 Gaming X with an Athlon 3000G, I plan to test the PSU with these parts plus an additional RAM stick.
I'll share updates shortly.
Additional information regarding the last application or reapplication of thermal paste has been noted. Observations about the system's startup and shutdown patterns also indicate possible thermal shutdown issues.
So here’s the update:
I tested the new PSU (Corsair) using its own set of cables along with a Gigabyte B450 Gaming X + Athlon 3000G and one stick of RAM. It functioned perfectly. Everything worked smoothly inside a cardboard box.
On the same box, I added another RAM stick, the GT 9600, and the internal speaker – it also performed well.
Following identical steps (all inside the box), I then connected the RGB controller (still inside the new case). The only thing inside was the case fan, and it lit up. I could enter the Gigabyte BIOS and confirmed both RAM sticks were detected – everything was functioning correctly.