I have seen this on every MSI 694D Pro 1.0 I've recapped. Between PCI slots 2 and 3, resides C390. The cap value stock is 1000uF 6.3v. Of course upon receiving the board, this cap is vented like many others. I recapped the board, of course replacing C390. I then would connect the board to my jig and burn it in for a while... Within the first 30 minutes or so, C390 would be vented again. I checked to make sure I installed it correctly, and the correct voltage. It was correct, so I assumed I had a dud for a replacement cap (Rubycon's, so this scenario was unlikely). I replaced it again, and tested again... Same result. Within the first 30 minutes, C390 vented again. Through this whole ordeal, the board was working fine.
At this point, I was puzzled... So I flipped the board over and read the voltage on the cap while the board was powered up and running the tests. On C390, I placed the '+' meter lead on the '+' cap lead, same thing with the neg leads. To my surprise, there was a -3.9v on the cap. I had to do a doubletake and make sure I had the leads attached correctly, and they were. There is a negative voltage on the C390 position when reading the cap position according to the polarity marking on the board.
I installed another Rubycon replacement, only this time I installed it backward. Opposite of the board polarity markings, and the board has been running flawlessly for over a week now, no more venting of C390.
Like I said, I've seen this on MANY MSI 694D Pro boards, so it was not an isolated case, or just a 'quirk' with one particular board. I will post some pics soon.
At this point, I was puzzled... So I flipped the board over and read the voltage on the cap while the board was powered up and running the tests. On C390, I placed the '+' meter lead on the '+' cap lead, same thing with the neg leads. To my surprise, there was a -3.9v on the cap. I had to do a doubletake and make sure I had the leads attached correctly, and they were. There is a negative voltage on the C390 position when reading the cap position according to the polarity marking on the board.
I installed another Rubycon replacement, only this time I installed it backward. Opposite of the board polarity markings, and the board has been running flawlessly for over a week now, no more venting of C390.
Like I said, I've seen this on MANY MSI 694D Pro boards, so it was not an isolated case, or just a 'quirk' with one particular board. I will post some pics soon.
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