Cardbus-compliant pcmcia buses might be readable, but they're
usually bridged from any real cpu bus and don't carry diagnostic
information. That would exclude most earlier and recent laptops
from consideration, since early ones weren't cardbus compliant
and few newer ones have pcmcia at all!

James Sweet wrote:

Isn't PCMCIA essentially an ISA bus? I suppose a diagnostic card could
be made, but laptops are not particularly modular, I've always found it
easier to just remove any accessories, swap the RAM out, if it's still
acting up then the problem is likely the motherboard in which case
there's not much that can be done.