REPAIRED ATARI 800XL memory test screen squares display

[uveprom]

I got this one in box, NEW, but when it turns on, starting showing red squares a lot, just 4 green squares,

just remove all the ram chips 4264, and place sockets, next place new samsung 4164b-10 ram, NOW systems works Ok,

next i test all the old chips 4264 one by one, for my surprise just one(1) chip is bad!

 

 

[Rybags]

That's all it takes. Each chip supplies 1 bit for every byte possible to access.

 

Problem is the stock memory test isn't very useful. A decent memory test if it knows your Ram configuration should be able to suggest which chip/s are faulty.

[tjlazer]

Usually you can piggy back 1 good ram chip on each one at a time to test to find which one is bad

[Kyle22]

Usually you can piggy back 1 good ram chip on each one at a time to test to find which one is bad

Yes, but that only works if the bad chip is open and not shorted.

[+mytek]

Wow that's a great looking virgin unit If you don't mind me asking, how much did it cost?

 

- Michael