As the title says, I only have 3.19 gb of RAM usable on a 64bit OS with 8 gb installed. I have checked my BIOS, it is up-to-date, but old. I have also checked Window's Resource Monitor, it knows 8gb is installed, but like earlier, can only use 3.19.
Yes I am positive it is 64 bit.
My motherboard is p45turbotwins2000. It recognizes that my RAM is installed.
I have 2x4 gb DDR3 sticks.
I just installed Windows 7 Home Premium 64bit. Nothing except Firefox has been installed.
All Windows updates are installed.
If you need anything past that, let me know. I'm at a loss.
Your first 3.19GB of RAM are your first, addressable in 32bit, memory locations. The rest is reserved for MMIO. Anything after that (your other 4GB), requires 64bit memory addresses. Normally MMIO is remapped and 64bit is used by default, your motherboard seems to not do that (for whatever crazy reason).