This image show valid/invalid configurations according to IBM:
Will this configuration pictured here work as well? This diagram is mine:
Exact configuration:
- CPU 1: 3x 16GB 1600MHz Dual Rank
- CPU 2: 6x 8GB 1333MHz Dual Rank
Here is a link to the whitepaper for context.
You don't mention what actual server and memory you're planning on using but given what you have that seems ok for a 56xx series box.