PC PSU
PC PSU
I'm trying to fix an issue with my PC power supply. It's a 24-pin setup, and the computer won't boot up while the power supply fan isn't running. I removed the supply from the PC and used a paper clip test—everything seems fine there. The fan is working, voltages are correct, and all measurements look good with a multimeter. My concern is the gray wire (PS-OK) signal. This pin shows 5V DC when measured to common, but when connected to the motherboard it reads 0V DC. Do I still have a power supply problem, or could the motherboard be the issue? Any advice would be greatly appreciated.
With the power supply linked to the motherboard, covering both the ATX 24 pin and any necessary EPS/CPU connectors, have you attempted removing the case switch from the formula and instead directly connecting the pwr pins on the motherboard to activate the power-on signal, thereby causing the PSU to power up? As described here:
https://www.gamersnexus.net/guides/2011-...tch-button
Additionally, these are the suggested procedures for testing, which go beyond merely using a paperclip.
See: https://www.youtube.com/watch?v=ixcWCrYpw3Y
I have attempted to bypass the power switch by connecting a jumper across its terminals on the motherboard, but this did not work. The power supply model is EVGA 750B3 p/n# 220-B3-0750. It has been operational for several years. The system uses an ASUS motherboard, with a PNY GeForce 1660 OC 6GB GDDR5 PCIe 3.0 graphics card and a 1 TB WD hard drive.
Absolutely terrible power supply. The B2 series were amazing. The B3 units were fully functional but completely useless. Relevant review details can be found here: I can confirm these B3 units were poor quality and should never have been sold or used by anyone with any system, regardless of specifications. Knowing the CPU and motherboard model would be very useful for assessing how long it has been in use and its likely initial condition.