Atari 2600/7800 Consoles Games Working?

[Casati]

I bought three Atari lots off Ebay recently, and have some difficulty evaluating the working order of the consoles and games. For instance, I have a Donkey Kong 2600 cart that displays a distracting screen pattern on my woodgrain and jr, but displays fine on the 7800 console. I bought another DK 2600 to replace it, and it displays fine on the woodgrain+jr, but doesn't play at all on the 7800. My Asteroids 2600 carts play fine on the woodgrain and 7800, but display a chopped, misaligned border on the jr.

When I buy a NES cart, it's easy to evaluate whether it works or not on my toploader because 99%+ of my NES carts play fine on it. But some of my Atari carts play fine on one Atari console but not another. It's not nearly as clear cut. Are the consoles just bad, that is, do Atari consoles in good working order play most all Atari carts fine, or is it just hit and miss with Atari carts due to the nature of the Atari consoles or the Atari carts?

[Mamejay]

Have you cleaned the cart contacts on the Atari carts?

Fist thing I would be doing is using some metal polish to get them nice and clean and try it again.
out of 150 carts i have had only 1 faulty.

Clean first and see how you go.