[QUOTE=mciahel;2617085]The software you were using reported “Wrong values reported by Bios”.
Crystal ball mode:
[li]The unknown diagnostic software you are using can’t handle the amount of RAM installed[/li][li]The unknown diagnostic software you are using can’t handle the flavour of Windows it is installed under[/li][li]Something in the BIOS settings is misconfigured[/li][/ol]
In case of #3; loading BIOS defaults (see motherboard manual for details) might help.
Some other device, like the internal VGA card, might have taken some of the memory for itself.