Issue with hash in Chess base GUI

[Nimzovik]

Hmmmmmmmm Historically I could use 1637 Mb of hash for my engines in chessbase fritz 11 gui on my 2 GB hash AMD win xp pro 64 bit machine.......for some strange reason the Gui only allows me to utilize 1309 MB now...... Doubt the Ram is bad. The GUI indicates I can use 1500+ M B but even when I try that procedure I still end up with only 1309??!!! Was up wi dat?