How to check the operation of the PSU without a PC?

Question

Iron

Good afternoon.
I have a PC with an ASRock motherboard that hangs on the splash screen of the motherboard. Tried to turn off everything except one bar of RAM and video card, the problem persists. Tried to rearrange RAM sticks from different manufacturers in different slots, but the result is the same. Resetting CMOS, flashing UEFI, did not help.
At the same time, if you call up the bootable media selection menu (which does not always work), then the PC boots up normally, after which it works stably without any errors in everyday work and under loads.
I sin on the motherboard, but I do not exclude possible problems with the PSU. Are there options on how to check the correct operation of the PSU without a second PC?
Thank you.

Answer 1

Connect the load to the PSU, start it, watch the levels and ripples...