Trying to repair a Powercolor 5500XT. I checked all the VRMs, found a short on the Vcore. I thought the culprit was a bad HiFet, as shown in the pic, I removed both Hi and Lo, only to find that the Hi was bad and the Lo was good.
Unfortunately, the short still present. So I lifted the inductors (open circuit) and measured. As you can see the top 2 inductors (Memory??) still reads short, 0.3 ohms. The other inductors reads around 30 ohms. And the bottom inductor (PEX??), reads 2.5 ohms.
Also I measured the caps to the right side of the inductors, they are short. The caps on the left side of the mosfets are good.
I'm not sure what to do at this point. I initially assumed it may be another shorted mosfet, but after lifting both Memory inductors, they both read short. So that would mean 3 mosfets total would have shorted, which I don't believe happened. also the caps toward the left of these mosfets reads good.
Please help. THanks in advance.
Unfortunately, the short still present. So I lifted the inductors (open circuit) and measured. As you can see the top 2 inductors (Memory??) still reads short, 0.3 ohms. The other inductors reads around 30 ohms. And the bottom inductor (PEX??), reads 2.5 ohms.
Also I measured the caps to the right side of the inductors, they are short. The caps on the left side of the mosfets are good.
I'm not sure what to do at this point. I initially assumed it may be another shorted mosfet, but after lifting both Memory inductors, they both read short. So that would mean 3 mosfets total would have shorted, which I don't believe happened. also the caps toward the left of these mosfets reads good.
Please help. THanks in advance.
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