Gigabyte R9 390X

[Gecko-EC]

Good Day to All,



I hope there is someone that can assist me with my GPU. Is does not startup at. Zero fan spin. GPU not heating up at all. I have checked all fuses and voltages that I can find. The one problem (if it is even a problem) is a reading that I am getting off a mosfet. Between Pin 1 of L1014 & Pin 4 of Q4026 ( PS_VDDC_UG5_R) gives me a reading of around 645-650 ohms. Between Pin 1 of L1012, 1013, 1015 and corresponding Pin 4 on Q4020, 4023, 4029 all give a reading of 7.73kohms

[прямо]

That is not the correct way to check for faulty mosfets.

Measure in resistance mode:
between the mosfet gate and source, also between the mosfet drain and source.

If you get anywhere near 0 ohm on either one of those measurements or even both measurements, you have a faulty mosfet.

Which I don't think what you have there.

An older generation GPU card that doesn't show any sign of life at all (no display and fan doesn't spin), is usually because 12V or 3.3V from the PCIe slot is not present.

If 12V and 3.3V from PCIe slot are present, then check the 5V.
If 5V is present, then check the crystal oscillator circuit (you need a 50MHz/100MHz oscilloscope)

For AMD R9 390X, you should have all of these present for it to boot:

12V and 3.3V from PCIe slot
12V from power supply
5V
1.8V
1.5V VMEM
1.0V VDDCI
0.85V to 1.0V VCORE
3.3V PERST (reset signal from PCIe slot)