Memory hole on quad core servers

Newer hardware seems to be showing less memory to windows than older hardware.

This is due to new CPU technology and something called the PCI memory hole. HP is some details on the link at the bottom of this blog.

But basically the new hardware in HP blades consumes some of the memory so windows has less to play with. This is obviously bad news in a terminal server environment where memory is usually the constraint for user numbers. Here is varying hardware and the amount of memory shown to windows.
All servers had 4Gb fitted. (and /pae switch make no difference)

BL20 G2 3.81 GB
BL20 G3 3.50 GB
BL25 G1 3.83 GB
BL25 G2 4.00 GB
BL460 G1 3.25 GB
BL465 G5 3.25 GB

See HP article c00883105