I have already done the known checks like e.g. fuse check, reset check, cartridge check, blind load comands, heat check on chips, etc., but to no luck
![Sad :(](./images/smilies/icon_sad.gif)
I have repaired tons of C64 and the C64 is known for a rather high PLA chip failure.
Now, which chip would you desolder and replace first ?
Jogi once told me every VIC-20 will produce a empty border screen if only the VIC is still in the board, but that would mean a lot of desoldering
![Wink ;)](./images/smilies/icon_wink.gif)
Does the VIC die often ? Or do the rams fail more often ? Or the CPU ? (it doesn't fail often in the C64, btw.) The kernel is socketed on some of them, so this one can be ruled out on 3 of the 4, I think.
Thanx for any repair suggestions !