I have an LC520 logic board (makes a nice upgrade for a Color Classic, with a 25mhz 68030, 32 bit bus, and 36mb RAM) that gives immediate chimes of death on powering on. This happens whether or not the board is installed bare (without memory sticks), and no matter what RAM/ VRAM sticks are installed (all sticks work in comparable machines from the era). Power-on tests have been conducted in a working LC575 that starts up fine from other logic boards, including another LC520 board that was sold on long ago.
So this one LC520 logic board that I have left is definitely bad.
I would prefer not to throw it out, so I wonder about the theoretical possibility of repair. There is a small quantity of onboard RAM (4MB) and VRAM (512k) soldered on the LC520's logic board, so my thinking is that one of the on-board memory chips is most likely what has died. POST checks RAM and VRAM right out of the starting gate, as I understand it.
Is a proper diagnosis possible or is it just guesswork?
So this one LC520 logic board that I have left is definitely bad.
I would prefer not to throw it out, so I wonder about the theoretical possibility of repair. There is a small quantity of onboard RAM (4MB) and VRAM (512k) soldered on the LC520's logic board, so my thinking is that one of the on-board memory chips is most likely what has died. POST checks RAM and VRAM right out of the starting gate, as I understand it.
Is a proper diagnosis possible or is it just guesswork?
