HP Vectra QS/20: System won't see RAM in bank 1

So, my Vectra QS/20 has two banks for RAM, four slots each. I have five sets of four 1mb sticks that all detect fine in the bank 0 slots and give the system 4mb of RAM. But when I try to put two sets in- four sticks in bank 0, four in bank 1- it won't even POST. Ive tried mixing and matching chips as well: no issues there, but only if I load bank 0. Once I drop sticks in bank 1, nothing. Monitor doesnt even get a signal. There are no jumpers on the system related to RAM that I can find.

Am I missing anything I can try? Or is there just something wrong with the board and bank 1 is borked?