chipmemsize A4000

[Piru]

8000 0006 means memory i/o error...

Nope, the CPU has executed CHK or CHK2 instruction with true condition (exception 6 generated).

Amiga programs don't use CHK or CHK2 instructions, so this means things are going horribly wrong at some point. However, because the Amiga is able to display a guru of some sort means that at least part of the memory is working fine.

[Piru]

There is no such thing as a double-sided SIMM. If it has two sides, then it's a DIMM.

SIMMs and DIMMs come in both single and double side flavors.

[Piru]

I was kidding.

Hard to tell with all those memory i/o errors...