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Mac 512k issues

tf 85e3

I just got this and when i power it on an immediately turn it off then on it does this for a second and goes away i think its the caps.


Well-known member
Isn't that just junk in the vram before it gets initialized? you normally don't see it when you just turn on the machine because the display isn't warmed up enough yet to make a picture.


Well-known member
Even though less frequent, ROM sockets on a Macintosh 512k can become corroded after nearly 40 years, which can sometimes cause vertical bars at startup. To address this, thoroughly clean the ROM socket contacts with DeoxIT contact cleaner spray and then carefully reseat the chips.

It's worth a try since it's a far more simple job than desoldering RAM chips on that motherboard.