In the Bios of my Mainboard is a feature called "memory remap" (or so) that I had to enable to get 3,5 GB of my 8 GB working under Windows XP 32bit.

Without enableing this feature I had around 2 GB too.

Hi, Jörg, made a remark about the memory remap feature in BIOS.

I've noticed this on my MoBo, too. BTW, it's a simple 'math', 2*32=4,2xx,xxx,xxx Bytes, in theory, but other hardware, like the GPU-CARDs, need some adress space too.
Andthen there is the so called PAE (Physical Adress Extension)(36BIT)

On a 64BIT OS, you've to switch this on, otherwise the same situation will occur, that is, you can't adress more then 3,2xx GByte (physical).

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