I'm using a X8QBE with 128GB RAM (16x 8GB). I'm running Win2k8 R2 64bit Standard edition. Windows only reports 32GB of RAM, where is the other 96GB?
Please note that Win2K8 R2 Standard Edition can only address up to 32GB. For more information you can check http://en.wikipedia.org/wiki/Windows_Server_2008_R2#Editions