4GB RAM shows up in WinXP as 3.5GB

Just a long shot but....1 stick could be bad. Try
loading up 1 stick at a time and see what each registers
as. Are you sharing any RAM with video?
>-----Original Message-----
>I have 4 sticks of ECC PC-2100 1 GB Kingston RAM
(KVR266X72C25/1G) and Windows XP only sees this as 3.5 GB
of RAM. As a WinXP MCP, I have been led to believe that
WinXP can support 4 GB of RAM, so what am I doing wrong?
>
>TIA
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