How many virtual partitions do the Power 750 and Power 755 support?
Initially, using PowerVM, the Power 750 can support up to 160 virtual partitions.
The Power 755 does not support PowerVM, therefore does not support any virtual partitions. However, it can support up to 32 dynamic partitions.
Update April 12, 2011:
IBM has delivered on the Statement of Direction for the Power 750: The Power 750 now supports a maximum of 320 virtual partitions.