AVP is a a featurecode that activates "micro" partitioning, and includes VIOS (Virtual IO Server) and PLM (Partition Load Manager). You pay the fee once per p5 system.

EDIT:  APV is Advanced Power Virtualization - why I wanted to remember it as Advanced Virtualization Power - well, I guess it was the late hour for me when I first replied.... Hope you managed to figure this one out ahead of this.

a p505 model, including AVP (Advanced Virtualization Processors). For training 1 CPU is enough except you will "never" be able to virtualize and have a partition with a 'dedicated' CPU. (as ivm/vioServer will always need at least 0.1 CPU).

And I'd recommend 2 disks, but one will work. Strongly recommend at least 2G memory (roughly 768M-1G minimum per partition for AIX or Linux, with ivm/vio server at 512KByte)