I have 4GB of SDRAM installed but only recognizes 3.25GB in "about this mac", any thoughts?

3.25GB 667 MHz DDR2 SDRAM

Leopard 10.5.2 on a dell inspiron 530, only issue was freezing due to the NIC card, problem solved with the USB LAN adaptor from my wii

Thanks

i know theres something about that 4gb ram. may want to read up alil. but i know how hard it can be to find info here sometimes. ill post if i come across something

If your kernel isn't 64bit enabled, and memory mapping isn't turn on in BIOS, that's what you will see. If you're on AMD CPU, stay that way will save you a lot trouble.