I recently upgraded to a 64 bit version of Windows 7 Ultimate to make use of all my 4GB of RAM, however when I still only have access to 3.25GB.
I have a Foxconn 946GZ7MA-8KS2H mobo, with a 2.5Ghz Q6600, I don't think I have the latest BIOS version, but Foxconn said not to flash it unless something is going wrong (I'm not sure this classes as something going wrong or not!).
I've read numerous posts online about integrated graphics and maybe even the integrated 7.1 sound card and LAN using the memory.
I tried the various options with memory in msconfig, unchecking the box and checking it with 4096MB and I still got 3.25GB.
I'm really not that sure about BIOS stuff, changing memory mapping (if my mobo can even do that?) etc, but I've take photos of the various screens and would really appreciate it if someone could point me in the right direction or confirm that this is what I'm stuck with! I'll post them in the following posts.