Powermac 6100 won't boot with additional memory

[morrisonmuzk]

Hi all...thanks in advance for reading!

Ok, so I've got a PowerMac 6100 that I recently recapped...I did the power supply and the logic board. Power supply is stable and meeting voltages.

I can always get it to chime, but I can only get it to get video and boot up if I remove any extra added memory from the 2 slots...it will only boot with the memory soldered on the logic board.

I've tried

1. booting with and without pram battery
2. swapping out the existing memory (at least the memory that was in it) and putting in different memory...always paired

Either way, I can only still get it to boot & video if I remove the extra memory (and have pram battery in).

I'm really stumped on this one...any thoughts or ideas? What am I missing?

thanks!