Question about Apple ///

[Adam Thornton]

I have an Apple /// that I've had for many years; it's never worked.

When you power it up, you get a checkerboard screen, where half the squares
are solid white, and the other half have a little mosaic pattern in them.

Looks like this:
https://share.icloud.com/photos/0NHNkEG9ssPsi65ojivBteKaQ

Does this failure mode ring any bells?  Obviously the video signal is being
generated well enough to sync a composite output.  Any idea whether I
should start by replacing the CPU or the ROMs?

Adam