F5F Stay Refreshed Hardware Desktop Load of PSU and motherboard setup

Load of PSU and motherboard setup

Load of PSU and motherboard setup

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Gingersplash11
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07-27-2016, 02:40 PM
#1
Hello, the computer hasn't been working properly for several days. The only indication of life is the power LED. Here are the details: the motherboard specs are I7 4770K, Asus Z87-A ATX, Gigabyte GTX 1070 mini Be Quiet!, 730W Gold (7 years old). The power supply unit appears to be inactive. I disconnected everything except the ATX, CPU power pins, and the front panel power switch, and replaced the CMOS battery without success. When the main AC is on, unplugging the ATX connector gives a steady 5.01V on the 5V purple wire and 2.85V on the green PSON# wire. When the ATX is plugged into the motherboard, both wires show 2.85V. (This seems normal, though I’m not an expert.) When I turned on the power switch on the front panel, the green wire didn’t drop, which would normally trigger the PSU to start. I checked the front panel power switch and found it works fine. I also tried connecting the green PSON# pin to a COM black pin on the ATX connector with a screwdriver, but it didn’t help. The fan runs and voltages look okay except for the PWR_OK grey pin, which sends unstable current between 2 and 5V. This might mean the ATX isn’t drawing power, preventing the PSU from stabilizing and sending a steady signal to that pin. I’ve tested the PSU on an older board with similar issues: pressing the ON switch or shorting its pin didn’t power it up, and the green pin didn’t drop voltage. On this new board, the 5V purple pin is unstable, fluctuating between 3 and 4.5V. Any suggestions on what to do next? Have I missed anything?
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G
Gingersplash11
07-27-2016, 02:40 PM #1

Hello, the computer hasn't been working properly for several days. The only indication of life is the power LED. Here are the details: the motherboard specs are I7 4770K, Asus Z87-A ATX, Gigabyte GTX 1070 mini Be Quiet!, 730W Gold (7 years old). The power supply unit appears to be inactive. I disconnected everything except the ATX, CPU power pins, and the front panel power switch, and replaced the CMOS battery without success. When the main AC is on, unplugging the ATX connector gives a steady 5.01V on the 5V purple wire and 2.85V on the green PSON# wire. When the ATX is plugged into the motherboard, both wires show 2.85V. (This seems normal, though I’m not an expert.) When I turned on the power switch on the front panel, the green wire didn’t drop, which would normally trigger the PSU to start. I checked the front panel power switch and found it works fine. I also tried connecting the green PSON# pin to a COM black pin on the ATX connector with a screwdriver, but it didn’t help. The fan runs and voltages look okay except for the PWR_OK grey pin, which sends unstable current between 2 and 5V. This might mean the ATX isn’t drawing power, preventing the PSU from stabilizing and sending a steady signal to that pin. I’ve tested the PSU on an older board with similar issues: pressing the ON switch or shorting its pin didn’t power it up, and the green pin didn’t drop voltage. On this new board, the 5V purple pin is unstable, fluctuating between 3 and 4.5V. Any suggestions on what to do next? Have I missed anything?

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