I have a computer running a BIOSTAR MCP6P M2+ 6.X motherboard using CORSAIR XMS2 4GB (2 x 2GB) Ram running windows 7 Home Premium 64 bit. When I first installed the Ram last year It showed up as 4 Gigs, however I recently noticed that it is only displaying 2.0 Gigs, in the My Computer Properties as well as CPU-Z, and in the POST. I have tested each stick individually in each slot and they work fine. However, when both are in only 2 gigs shows up. What might be the cause of this?
Also the Bios is up to date.
More aboutstick showing
Please post the exact Corsair part number and revision number of your MOBO.
This is what I know, here are the links to the very parts in case I didn't provide the info you requested.