AMG
Member
I have a Defender board that gets a RAM failure on every cold start. All RAM chips have been replaced with new 4164's (and power adapter) with no change. But once it's running, it passes the RAM test, and if I hit the reset switch I get the "initial tests indicate unit ok" message. And one time I accidentally turned the machine off and on with only about 3 seconds in between (I would normally never do that), and that time it also said "unit ok". I tried that again a few days later just as a test, and got "unit okay" yet again. The game plays fine after the initial failure message, but every time it starts I get the RAM failure. The machine has a switcher, and the RAM chips are getting 5.02 volts measured at the chip. Any clues what could cause the powerup RAM test to fail?

