A nice zebra pattern on my screen, frozen right away. I've tried applying pressure to them while turning the system on (which is a bit more difficult with 4 compared to just pressing on 1 ROM), but not getting it right.
I suspect its contacts but it might also be an issue with my SE/30 (eg. failed U-something). The SIMMs do not fit snugly like the older ones. Mailing the SIMMs to a friendly forum member who will try them in his SE/30.
I did manage to pull 4x4 with parity from my box of collected junk that work just fine, so I'm at 32MB now.