Question I bought a broken r9 390x for cheap has the 6 pin connector grounded

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Richez

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Jul 1, 2015
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I bought a broken asus strix r9 390 for 30 bucks on ebay. The card itself is in great physical shape but doesnt boot when in pc. When there is no pcie power plugged in it boots blind, when the 8 pin pcie connector is plugged in it does the same, But if i plug just the 6-pin pcie connector in the psu trips. The fans in the pc just turn on for about half a second. Im fairly good at soldering on pcb's and i have a rework station if it is something i can replace. I could use a hand identifying the issue with the card
 
im pinning tabs on my browser for all the articles you have sent me for reference as well as the vrm thanks but there is an outlier here for the resistance

http://prntscr.com/s8eyez
i checked every other vrm in the same way and nothing showed on the meter but these came up with a result

The “000” black piece is a fuse. The result should be 0Ohm. I’ll have a closer look during lunch :)
Resistor code table.
 
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Richez

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Cool, now you need to find out the value of the capacitor you are missing... The sad part is that it has to be off the board to measure.
yea im not taking apart his card lol he did say he was upgrading soon but that doesnt justify taking apart a perfectly working card for a next gen that performs just as well lol im sure there is another way to find the value of that cap with some research sadly there are no schematics for these cards if there is anything similar it would be good to have. Hopefully supplies come in soon as well its been taking a while already
 

Richez

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Cool, now you need to find out the value of the capacitor you are missing... The sad part is that it has to be off the board to measure.
i bought a tool to test capacitors on the board it looks like a set of tweezers when i get the chance i will get a reading on my friends r9 290 and also i ended up buying a strix rx 570 for the time being so im not stuck with a weak graphics card i wasnt able to get the supplies the order was cancelled for some reason and the same goes for the soldering iron im stuck without supplies for the card but will be coming back to work on it some time
 
i bought a tool to test capacitors on the board it looks like a set of tweezers when i get the chance i will get a reading on my friends r9 290
Great! You still have to at least move one leg away so you only read the value of what you want and not other things it is connected to.

To use the wait time, you can order those other parts you need to get the VRM back working (3555s).
 
Oct 28, 2020
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Sorry for bringing this post back to life but i could really use some help... I have a failing 390x Strix DCIII(same exact pcb as the one from this post) that has no artifacting or weird screen issues... The card will crash/restart the driver randomly and sometimes even black screen and then reboot the whole system...Even seen it completely hard lock the whole pc while gaming or watching youtube videos(sound looping too). I downloaded HawaiiBiosEditor and underclocked my core to 900mhz and my ram to 1000mhz and it doesn't seem to help...The card can run the heaven benchmark for 1 hour straight and then crash in like 1 minute(temps under 65c). Even overclocking the card doesn't seem to crash it easier so i guess it's not the core... I have been using it in the past with a waterblock and no vrm cooling whatsoever(for about a year), could a failing VRM cause this?The board seems to be weird around the vrms area (like stained) but looks nothing like something was fried...Really frustrated, can't afford to get a card right now and my old 6970 can't play anything at this point :( i repair phones for a living and have a rework station and fairly good soldering/bga skills, just not good pcb diagnostic skills... For some reason it's stuck in my head that this is either a memory issue or a failing vrm... ANY help from anyone will be greatly appreciated!
 
.The card can run the heaven benchmark for 1 hour straight and then crash in like 1 minute(temps under 65c). Even overclocking the card doesn't seem to crash it easier so i guess it's not the core... I have been using it in the past with a waterblock and no vrm cooling whatsoever(for about a year), could a failing VRM cause this?The board seems to be weird around the vrms area (like stained) but looks nothing like something was fried...
Your description suggests that there might be a problem with the PSU. Try running OCCT for only the GPU, and then the PSU stress and see at what point will it fail. Downclocking helps bringing power consumption down.
P.S - even though it is the same card, you should start a new thread, to keep things organized.
 
Oct 28, 2020
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Thanks for your reply :) My PSU is a 850W coolermaster M2... I also tried the card in my old Z800 with 1100W PSU and also tried running the card with 2 psus(one for the 6 pin and one for the 8 pin) It will also crash in lower clocks, even 800mhz core and 1000MHz Vram :/ There’s something wrong with the hardware for sure, this is not driver or PSU related... Even in Ubuntu live mode the card will randomly give black screen after some minutes doing nothing intensive(slightly warm to the touch)... Thank again for the reply :)
 
Thanks for your reply :) My PSU is a 850W coolermaster M2... I also tried the card in my old Z800 with 1100W PSU and also tried running the card with 2 psus(one for the 6 pin and one for the 8 pin) It will also crash in lower clocks, even 800mhz core and 1000MHz Vram :/ There’s something wrong with the hardware for sure, this is not driver or PSU related... Even in Ubuntu live mode the card will randomly give black screen after some minutes doing nothing intensive(slightly warm to the touch)... Thank again for the reply :)

If you are certain about the card being the problem, there are no easy fixes for intermittent hardware issues. Getting the equipment and consumables is far more expensive unless you already have access to them. Considering the age and the price of this card, getting a new or used but more recent card would be your best option.

For diagnostics, I would run GPU memory check and lift VRM shoulders to check them. Again, the price of this GPU is not worth the labor.
 
Oct 28, 2020
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I agree with you man but I’m really broke right now and the prices are all over the place... Getting the same performance out of another card will cost me upwards of 150€... People are selling 580s for 220€ and 1080tis for 450€... Can you recommend a memory test application? Also by vrm shoulders you mean the actual chips? I can do that no problem, like I said I have a bga rework station...
 
I agree with you man but I’m really broke right now and the prices are all over the place... Getting the same performance out of another card will cost me upwards of 150€... People are selling 580s for 220€ and 1080tis for 450€... Can you recommend a memory test application? Also by vrm shoulders you mean the actual chips? I can do that no problem, like I said I have a bga rework station...

Well, in my opinion, time and effort would be significantly more than the numbers you mentioned.
For hardware diagnostics, I would
  1. check resistances on all power buses (pcie, pcie controller, memory, gpu, etc..) and see if something catches your eye.
  2. Check individual shoulders (involves removing coils from every other shoulder's output as they are interconnected) looking for a dead horse. If you have a thermal imaging device (flir for example) you can check and see which phases are working and which are not without taking stuff off, just by heat distribution.
  3. On individual phases check for proper impulses and levels with scope.
  4. Check the controllers and couplers for proper signals

For memory tests, there is specialized software but it is not available to consumers. Instead, you can try Kombustor with artifact scanner (for example), that will test some memory.
Besides memory and power delivery issues, since those boards run hot, there might be partial IC separation (either memory or the GPU or the GPU die... those can be solved by reballing. Also might be a few caps degraded in the decoupler circuitry, causing power starvation or dumps that cause crashes... and that will take a lot of time to find, even when having a boardview for this exact board version and revision (pm-d you a link for the one I have access to).

Good luck.
 
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Oct 28, 2020
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Kombustor won’t really help cause the gpu will crash by the time I have any useful data concerning the vram... I did search for Vram memory test but I also didn’t find anything useful.... I’ve heard about this specific problem at least 5 times by various people so I figured it could be something known for 390x’s... Gonna investigate more, thank you for everything I will surely use all this info 😇