I wouldn't chuck it, but then I like old stuff. This is the deciding
factor, really: are you wanting to use it for fun, because it's an old
computer, or do you just want a computer to use? I had a Commodore 32
which was great fun to use, but ultimately I ran out of space and gave
it to a guy who collects old computers. It depends on your interests.

I had the same problem with a SPARCstation 4 a year or two ago. It
turned out that one of the three RAM modules was bad, but you say
you've already checked that? When I got my Ultra 2 I gave the
SPARCstation 4 to a guy who employed it as some kind of server. It was
only 110 MHz but he was still using it last year.

Best wishes,

Chris