Hi, I am trying to repair this R9 380 by XFX.
Fans works, no video .... but it's not the gpu ... there is no voltage
on the ram.
Looking at the board, there are two APW8722 near the two PCI-e power connector.
Checking the datasheet, there are two interesting pins: BOOT and COMP.
If COMP is pulled down, the IC shut down.
The BOOT honestly I am not sure, but it should give a voltage bump at
the beginning to initiate the voltage regulation.
VCC is presente. The two MOSFET connected to the IC are good.
There are not evident shorts checking here and there with the multimeter .. and also checking with a finger if something is hot results in nothing obvious.
Any idea? I was guessing the APW8722 was faulty but since both of them have the same behaviour I am inclined to think there is something else who stop them to regulated the voltage, maybe pulling down COMP ...
At the beginning I also guessed there was something wrong with the bios but I check the chip with my ch341 and the bios was ok ... but there is no voltage to the chip when you star the board !!
Fans works, no video .... but it's not the gpu ... there is no voltage
on the ram.
Looking at the board, there are two APW8722 near the two PCI-e power connector.
Checking the datasheet, there are two interesting pins: BOOT and COMP.
If COMP is pulled down, the IC shut down.
The BOOT honestly I am not sure, but it should give a voltage bump at
the beginning to initiate the voltage regulation.
VCC is presente. The two MOSFET connected to the IC are good.
There are not evident shorts checking here and there with the multimeter .. and also checking with a finger if something is hot results in nothing obvious.
Any idea? I was guessing the APW8722 was faulty but since both of them have the same behaviour I am inclined to think there is something else who stop them to regulated the voltage, maybe pulling down COMP ...
At the beginning I also guessed there was something wrong with the bios but I check the chip with my ch341 and the bios was ok ... but there is no voltage to the chip when you star the board !!
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