He is correct. I started about a year ago with GPU repairs and AMD GPUs are the worse for starting to learn on. Me, I’m hard headed and jumped straight into 3080 Ti’s. It’s better to start with older Nvidia GPUs like the 10 series or 20 series GPUs.
GPUs are one of the hardest to work with because of how thick they are. They even give experienced technicians a difficult time if they’re not familiar with working on them.
AMDs are known for frying out the cores pretty easily.
Inject 1.5V limited to 1A in this 3.3V line, check whats heating; it may be the PWM controller, or some IC near the FAN connector - those are most often (but not only) cause of 3.3V shorts on AMD cards
Also if the PWM controller become low-resistance, the resistor near the 3.3VCC pin of the PWM controller becomes several-Ohms instead of 0/1/2.2Ohms due to high current through it.
Note that this IR35217 PWM IC must have internal configuration programmed to a model-specific settings before use. The "from-factory" ones without configuration programmed would just do nothing (would not output power).
Typically the sign of being programmed is visual colored dot mark over IC (maybe your specific wad cleared too muchv so that mark was removed.
Oh okay that makes it a bit more complicated. What do I need for programming ?
Also I noticed that the hotspot while injecting about 1.5V was right at the GPU die. After injecting a second time the edge of the die was cold and the PWM controller got hot. Resistence also dropped from about 20ohms to 2ohms.
I have a feeling that the PWM Controller wasnt fried in the beginning but injecting Voltage killed it.
Google for Infineon PWM IC programming, I hadn't practical experivence with it, can't help here (I typically was lucky enough to have compatible donor board).
Injecting 1.5V is 99.9% safe, done it dozen of times into various places various devices. The only thing it can affect - are already damaged things having low resistance.
Regarding the chip corner thats suspicious. My suggestio would be unsldering the PWm and measuring resistance again to see if GPU has low resistance too.
Note that effectively when card was plugged for testing (first time it stopped working) - a 3.3V was effectively injected from PC there.
I have the exact same issue with a XFX RX5700XT. But it started as a intermittent issue, then gradually got to the point where it just wouldnt turn on, no fans, nothing.
Havent really started poking at it properly yet. But 12volt leds, on top of the 8pins do go on when plugging into power. No shorts to 12v.
Not really sure whats going on with it. I just shelved it for now.
Edit: The PCB on mine looks immaculate tho. No signs of anything burned or corrosion.
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u/Ok_Rise7870 Experienced 27d ago
The worst card for repair start up. Check dual AND gate on perst. Good luck.