View Full Version : NES video fills with garbage longer system is on
Compute
09-12-2011, 09:50 AM
Hey all, I'm curious if anyone has run into this:
On my NES, everything seems to play fine at first. After a while, the screen will start to fill up with 'garbage', the sprites will turn into other sprites, letters, etc. The games play fine in this state, we even managed to get pretty far in Contra without being able to tell what was what. I haven't busted out the meter yet, but I'm guessing a cap will be the issue. Any ideas where to start?
APE992
09-12-2011, 12:05 PM
The video bus runs through the cartridge connector.
A capacitor isn't at fault and there is absolutely no reason to suspect one at this juncture.
Gameguy
09-12-2011, 12:06 PM
Sounds like the video encoder could be dying, if it only started up with everything looking screwed up I'd say it would be dead for sure.
APE992
09-12-2011, 01:04 PM
Sounds like the video encoder could be dying, if it only started up with everything looking screwed up I'd say it would be dead for sure.
That is an interesting thought, maybe it is dying. The NES obviously doesn't get very hot but thermal expansion does take place. As I said a post earlier the video bus runs through the NES connector (really a bad design choice) which has caused me problems in the past that sound similar to this. Usually a cleaning/reseating of the connector fixes it for me.
But if that doesn't work the solder joints on the PPU might need a reflowing or maybe the RAM as well. The PPU is largely responsible for outputting video and not so much with the retrial of data from the cart to push it into RAM for manipulation. Corruption in my experience is a RAM or cart connector problem.
Heavily leaning on connector problems myself. Cheap and easy to fix and diagnose by comparison.
Compute
09-24-2011, 08:33 AM
I was about to re-post this, then I saw I already posted it last week. Thanks for the input. I didn't know that video is routed through the cartridge. That would explain why it happens more on some games than others. The only thing is that it doesn't happen right away. It occurs gradually and gets worse. I'll have to play around with it more when I get a chance.