I bought a SHVC-CPU-01 board, it works fine, at least for a few minutes, sometimes hours. Then suddenly i see the screen glitching out and it goes black. Sound continues playing. Reset doesn't bring it up again. Powering it off, leaving it off for a few moments, sometimes minutes, and it is able to boot up again.
7085 seems to output 5V according to DMM.
Reset button seems to work fine if the console runs normally, eg before crashing/blackening out.
So far I tried:
* changing the audio module (didn't expect that to be the culprit, was it was easy and fast): no change.
* changing the cart slot: at first it ran for hours, but today it blacked out again, so that wasn't the problem.
Next suspects are the capacitors, but I'll have to wait for it a little longer since the seller may resend a board, so I won't be doing any soldering on the board before that has been sorted out.
Anyone experienced similar behaviour or has any tips for repairing?
I would suggest bad caps. The two complete SHVC units I have are just black screen, and they quit working while in storage (the original one I had also died in storage.) I bought a SFC from Japan that worked for about a week and then it stopped working the next time I powered it on. So I wouldn't rule out bad caps. The only working SNES I have is the GPM-02, and it's just a bit dark, but that might just be the s-video cable.
Any other hardware I would normally suggest something thermal, as that is the trademark of overheating.