Gigabyte 2080Ti is not displayed (core open signal is not generated)

Gigabyte 2080Ti is not displayed (core open signal is not generated).

Gigabyte 2080Ti doesn’t display it. After the graphics card is removed, check the resistance of each inductor first. No problem is detected. The current can only be up to 000 mA with the conversion board. This current core is not working, and the voltage is measured when it is powered on. ……

[Fault model] Gigabyte 2080Ti

[Fault phenomenon] is not displayed.

[Maintenance process] I received a machine sent by a customer for repair, the model of which is Gigabyte 2080Ti, and the fault is not displayed.

Gigabyte 2080Ti does not show Figure 1.

After removing the video card, first check the resistance of each inductor. No problem was found. After checking the down current with the conversion board, it can only go up to 00mA. This current core is not working. When the power is turned on, the down voltage is measured, and it is found that 12V, 3V, 5 V and 1.8 V are all normal, but the power supply to the core is gone. Find it directly.schematic diagramCheck the condition of U823 for the position of core power supply, and find that the EN signal PS_NVVDD_EN is not available.

Gigabyte 2080Ti does not show Figure 2.

Then move on.

Gigabyte 2080Ti does not show Figure 3.

Tracing forward, it is found that the voltage of pin 2 of U44 is 1.8V, and the voltage of pin 1 is 0. This is an AND gate, and it is necessary for pin 1 and pin 2 to be at the same height to generate EN. Then, analyze the generation conditions of pin 1, and measure the resistance value of pin 1 first, which is more than 400, and there is no disconnection and short circuit.

Look at D2 and find that there is a NO STUFF in the front signal, which means it is not installed. Then look at D1 directly.

Gigabyte 2080Ti does not show Figure 4.

THERM_OVERT is a temperature control signal, and the measured voltage is 3.3V normally, so leave him alone, and then check that the voltage of PS_NV3V3_EN is 0, which is definitely abnormal, and trace the generating conditions of PS_NV3V3_EN.

Gigabyte 2080Ti does not show Figure 5.

When we found U40, we found that there was voltage at pin 1.2 and no voltage at pin 4. When we measured U40, the power supply at pin 5 was normal and the resistance at pin 4 was normal, so the problem was obvious.gating circuitI can’t find a replacement to directly short the 1,4 pins, and then power on to see that the core has been turned on and the power supply has come out.

Gigabyte 2080Ti does not show Figure 6.

[Maintenance result] After the graphics card is installed, the startup test can be successfully lit, and the baking machine pressure test is normal for half an hour after entering the system test, and the maintenance is over.