HELP! Have a memory hog in Win2k server

HELP! I have a memory hog!
Recently my Dell PowerEdge 2600 server running Windows Small Business Server 2000 has started limiting the available memory to 256MB at boot. There is 2GB of memory installed however Windows only sees this limited portion, whereas Dell utilities show full memory is functioning correctly. Microsoft latest patches have been applied. If anyone has any input on how to correct this it would be GREATLY appreciated.

Katie – forgive me I’m new