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My NES (NTSC) doesn't seem to want to turn on any more, I just get a white (or possibly very light grey) screen. Trying to boot up my PowerPak which, until very recently, was working fine.

Any ideas?

Clean it? Replacement connector?

I've had two units with the "light gray screen of death" issue, and on both of them I attempted to replace the angle connector, but with no luck. So one day I finally had enough and scrubbed the board contacts with alcohol and steel wool, and it worked like a dream

I would recommend separating the cart bay to motherboard connector and cleaning with cotton swabs and 80% alcohol. The steel wool was a bad idea (I was frustrated and thought it would never work again anyway) and did damage the connectors a bit.

Disclaimer: I sold that unit to a local resell shop shortly thereafter (decided famiclones were way less of a hassle ) so I'm not sure if that was a long-term solution or not.

I have a NES that makes a burnt plastic smell if you leave it powered on. Also I believe the CPU gets really hot. It does display a stable blank picture for awhile but then it starts going bonkers after awhile. I guess the CPU is fried and maybe something else is wrong with it. It was never hooked up with an improper power supply, it's possible it may have been zapped by static electricity at some point.

When a NES doesn't work it could be a few things. Bad caps or maybe bad generic ICs can be replaced. But if your CPU or PPU dies it's toast. I'm guessing if either the CPU or PPU dies they will get very hot when powered up. I'd say repairing or getting a working original system is much better than messing with clones.

Ive found scotch pads to be a much better solution than steel wool

MottZilla wrote:I have a NES that makes a burnt plastic smell if you leave it powered on. Also I believe the CPU gets really hot. It does display a stable blank picture for awhile but then it starts going bonkers after awhile. I guess the CPU is fried and maybe something else is wrong with it. It was never hooked up with an improper power supply, it's possible it may have been zapped by static electricity at some point.

Have you tried replacing the 20+ year old thermal compound between the voltage regulator and heat sink? Sounds like could be a cause if something inside is obviously getting super hot.

Honestly, for now I see no reason not to assume it's a dirty/loose connector. These things get dirty over time, and 99% of the time it's the issue.

Thanks for the replies!

As far as I know, nothing is overheating but ill take the case off and check later.

I'm pretty sure the cart connector is quite new (well, only 3-4 years) but ill give it a clean.

I gave up on the deck loaders due to the finicky cart connector. Even with a pristine connector and brand new cart I'd have to futz with the thing to get it to work right, and it drove me nuts. I guess I'm just impatient

Although the inverted duty cycles in the clones make me sad. I find myself listening to NSF's of Mega Man 2 while playing on my TV And TMNT is especially bad, but since I've beat that game finally I don't have to play it anymore

MottZilla, have you tried measuring the VCC voltage on the CPU and PPU? If the console is closed, try measuring the voltage on the controller port. A damaged regulator may output a slighty higher voltage, and higher voltage means more heat.

Weimans the games you play always, and clean the connector with alcohol/water and a tooth brush. Also weimans the system connector. Iff that doesn't fix it and they play the first time, new connector time. And DO NOT PUSH THE GAMES DOWN. That's important if you like your connector not ruined.

And yeah, what he said, make sure caps are okay and the regulator is well, regulating.

To be clear about my extra NES that doesn't work. The lockout chip does function and will cause the blinking light when the cart isn't set right or dirty. But no game cartridges will play, they are not dirty. I even tried a new connector. The system just has a gray screen and after time you smell that smell and I seem to recall one of the chips was hot, I believe the CPU.

I did not check the voltage regulator. I guess I should look into it again and see if it's possible to figure out what is wrong with it. But I think that one of the two primary chips is probably toast. If you disagree and think it's more likely a regulator issue or something else let me know. But the system basically outputs a stable blank picture, though afterawhile I seem to recall the picture started having problems so maybe there is an issue with the regulator. It was an extra system so I'm not worried about it, I have a working NES console. This spare had a case that was severely abused and missing the door and part of the case that would have been required to replace the door.

MottZilla wrote:But I think that one of the two primary chips is probably toast. If you disagree and think it's more likely a regulator issue or something else let me know.

CPU getting hot like that is probably one of:

• Bus conflict
• Overvoltage
• Permanent damage (causing an internal short)

With those symptoms, it could be basically anything on the board (well, not the NT RAM). You said the image eventually goes bad too; that vaguely implies checking overvoltage first.

I've found the new connectors to be shitty brand new. Soaking them in isopropyl alcohol, then repeatedly sliding them onto and off of edge connectors made them work much more reliably afterwards.

lidnariq wrote:

MottZilla wrote:But I think that one of the two primary chips is probably toast. If you disagree and think it's more likely a regulator issue or something else let me know.

CPU getting hot like that is probably one of:

• Bus conflict
• Overvoltage
• Permanent damage (causing an internal short)

With those symptoms, it could be basically anything on the board (well, not the NT RAM). You said the image eventually goes bad too; that vaguely implies checking overvoltage first.

So would you doubt that it's actually beyond repair then? Whenever I find the board I'll test the voltage at the regulator and at the various chips.

I wouldn't worry too much about the thermal compound as there is none on the top loader and its bolted to an aluminum heat sink. I'm not saying a regulator won't go bad for other reasons and cause problems though.
I've fixed several grey screen top loaders, all had either a bad cpu or ppu, replacing it with a known good one from a front loader donor board resulted in a working top loader. My guess is internal shorts in the chips are causing the end fail, but what causes the internal short is anyone's guess.