Gigabyte H81M-S1 repair without CPU power supply

Gigabyte H81M-S1 repair without CPU power supply

Gigabyte H81M-S1 has no CPU power supply. The IT8620E trigger is normal. After replacing the power supply chip ISL95812, the fault is eliminated.

Machine model: Gigabyte H81M-S1 REV: 2.1

Fault phenomenon: no CPU power supply

Gigabyte H81M-S1 repair without CPU power supply Figure 1.

Maintenance process: The initial failure was no CPU power supply. All power supplies are normal and CPU power supply chips are normal after one operation. But the sad failure occurred at this time.

Gigabyte H81M-S1 repair without CPU power supply Figure 2.

Measuring VR_ Due to carelessness when turning ON, the multimeter head touches the resistance beside it. As a result, 12V voltage is directly connected to VR_ ON is on. VR_ The ON is sent by the IT8620E, and the computer is no longer triggered. After replacing an IT8620E, it can be triggered, and then go to test VR_ ON, and the IT8620E burns again, but if it can be triggered, the power is lost. The IT8620E trigger is normal again. Measure the CPU voltage. The voltage rises from 0.8V to 3V. Fortunately, I did not power on the CPU. After replacing the power supply chip ISL95812, the fault was eliminated.