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Question Trying to fix an R9 390x that almost works.

Jul 9, 2020
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A couple years ago my old boss gave me his R9 390x because it stopped working for him. I just now got around to trying to fix it. I can get video out from one of the displayports, but not the other two displayports, the hdmi, or DVI port. When I start the computer with a display connected to the "working" displayport, I get to a windows logo and then just a blank screen. With the card removed and the display connected to the motherboard (asus Z87-PRO), the computer works normally. Same scenario with my backup motherboard (asus m5az8l-m/usb3). I don't actually have a displayport cable, so I've been using an HDMI cable and an HDMI to displayport adapter.
I did some investigating on the board with my multimeter and found that the voltage for the VRAM is at about 1.6V, but the max recommended voltage for the sk hynix h5gc4h24ajr is 1.5 V. Could that be an issue?
I don't see any broken or missing components on the board. There is a resistor that looks like it might have over-heated. I took a look with my Seek camera and it gets hot on start-up, but then cools down after a minute or so. It's the 16k ohm resistor for the compensatory circuit for the uP1664 (VRAM voltage controller). I removed the resistor and measured it: almost exactly 16k ohms. When I measure across it while the card is running, I get 0 V dc, and nothing on my oscilloscope. For the life of me I can't find a datasheet for the uP1664. Just what's on the uPI website: https://www.upi-semi.com/en-article-upi-362-2104
Is there a way to check how the card is working with HWiNFO? When I have the R9 as well as my good, working card connected to my mobo, HWiNFO only shows info for the good card. And without the good card and the displays connected to the mobo, the computer seems to default to the graphics card. I assume that's normal, but it leaves me in a bit of a pickle.
Thanks, folks!
 

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