Minor SNES Graphics Corruption

Hello! I'm new here because I found these forums while Googling around for information on SNES VRAM chips. I see that the community is still active and friendly, so I figured I'd ask for some expert advice.

A few years ago, a friend gave me his (rather yellow) NTSC SNES, which I took apart to find is a SHVC-CPU-01, and it's the older revision with the large power input capacitor. In general, it runs perfectly fine. The only problem is that most sprites have minor corruption on the right side, usually in the form of a column of white pixels, but they can sometimes be black.

I've linked a picture of the SMW title screen showing that the foreground objects are not affected by this corruption, as well as a picture of the first stage and a video of Mario jumping around to show how the artifacts shimmer in a rather annoying fashion and how sometimes the pixels run down the left edge of the screen. It looks like the title screen doesn't suffer from the problem at all, but in reality the in-game objects behind the title have a very faint version of the white pixels.



This issue only happens to this console with any game, including Star Fox and the Super Game Boy. These same cartridges work fine in my mini SNES.

My theory is that one of the VRAM or PPU chips has gone bad, but I'd like some additional opinions before I go attempting to solder a new one on. Oh, and I'd like to point out that the area around the PPUs and VRAM looks absolutely pristine with no signs of corrosion or damage.

 

The pictures don't seem to be showing up for me. Are they working for anyone else?

 

Not for me. Even when opening them in a new tab, Google forces me to log in and then just shows me a stop sign. Seems like someone has some fixing to do.

 

My mistake! I've moved them to imgur now.

 

Did you make sure that the cart slot is clean? A run of the burn-in test could help in diagnosing, though obviously requires a flashcart. I'd take a look at the surface-mount caps and check for leakage/broken traces there as well... not saying that's necessarily what's going on here, as weak caps would probably show as a dim/flickering picture in the first place, but with how often these types of issues pop up on the SNES I do wonder if caps (or lack thereof, by design) could be responsible for the odd blown PPU or RAM chips.

 

Hi everyone.

I wanted to ask my question here rather than creating a useless thread.
Do you guys have any tips to detect if the cart slot on a SNES (PAL) is soldered or not ?
I have attached a picture so you guys can analyze the body of the console and judge by yourself. I Tried to pull it out with more or less force. The console has not been cleaned for a while so it might cause some diffculties to pull it out? Anyway nothing came up so I just left it as it were.
I have another SNES with a "Plug and Play" slot and I barely forced on it to remove it.

Thanks !

 

Look on the back of the motherboard and see if its soldered? lol...

 

I had a Pal snes that did something like that once. It was a dirty connector. Cleaned it out and it worked fine again.

 

Hi

Nice try But not that simple. Every SNES has it's cart connectors soldered to the bottom of the motherboard. But some models allow a little more disassembly of the cart slot from the top of the motherboard, not underneath. On a first look you would'nt know if it's unplugable just by looking at the bottom of the mb.

 

oh I see. I was unaware of that.