Sooner or later (as most of you have probably noticed) you will get neverending blinking screens of DOOM. You think "oh well, the connecters are "dirty." Chances are, you're wrong. You might have been right the first time, like 10 years ago, but not anymore. So what do you guys usually do? You blow on the game. Do you guys know what the little water droplets that condensed on the game does to the copper/brass connector inside your NES? That's right, it corrodes your connectors! The corroded areas of the connectors dont usually transfer electricity through them quite as well as a nice shiny copper connector will. This will make some pins not connect to the connector, causing your screen to blink!

There aren't any simple ways to fix this problem. All i really do to fix this is clean the system connector with the cleaning kit, then clean the games too. Sometimes it helps! Not much you can do!