This is in fact, very sad. You need a motherboard that supports up to 8GB.
My motherboard is expandable up to 4 gigs. The BIOs reads 4 full GBs of
RAM, But the 64bit OS only reports 3.25gb. I was runnning the 64bit OS with
3 gigs of RAM (2 gigs, 2 512s) and it reported the full 3 gigs. Junk.

"Josh" wrote:

The sad but true facts:

*You need a x64 processor,
*x64 motherboard with RAM remapping support (anything new or AM2 compatible)
*x64 motherboard must support, not have, 8GB of RAM, but can have 8GB if you
wish,
*x64 vista OS.

Most cases you just need to move up to the x64 OS, this gives you more
performance than a 32bit OS, i personaly gained an extra 294 3D benchmark
points from the switch. Your also pretty much assured to meet the above
requirments if your system is new, but some older systems may work, don't
forget to backup OS BEFORE updating, as to evade any errors or no gos. If you
have the original version of windows XP (no service packs) and the upgrade
pack of vista you can do a full clean install of vista 64bit (if you have
ulitmate).