I don't think I can actually change that on an OEM Bios, perhaps it's time for a new mobo. However, my mobo is 2-3 years old, could it be a possibility that the DIMM slots only allow up to 4GB per DIMM? Quite possibly - I can't find anything on that board other than that it's from a pre-built system. 8 I assume your new RAM is 2x8? If you want to confirm this theory, just put a single 8gb stick in and if it says 8 with 4 usable or whatever then that's probably what the board is limited to. Then add the second stick and it should double your first result. Whenever I tried to load one of the sticks it would just show up as 1GB in the BIOS and it wouldn't let me boot. Curious when you did get into BIO's was there an option to select XMP Profiles? Also, are you expecting a total of 20GB of RAM to be used with your new RAM. 16GB + 4GB ? I see that you have Windows 7 Home Premium which has a Max of 16GB Ram on a x64 system. I do find it odd that it's limiting at 4GB with all your RAM installed; because, when I checked max RAM for Windows 7 Home Premium for x64 it said 16GB which makes sense while the x86 is limited to 4GB but youre running 64bit. http://msdn.microsoft.com/en-us/library/windows/desktop/aa366778(v=vs.85).aspx#physical_memory_limits_windows_7
Haven't seen XMP Profiles, probably because my BIOS is pretty locked down. I wasn't expecting 20GB but the system wouldn't boot without my old 4GB of RAM. I tried testing around and it seems that if I try to enable memory remapping, my BIOS loads the full 16GB (without skipping) but when I start up Windows, it just gives me a BSOD. I'm 90% sure it's my motherboard only allowing 8GB ( 4 x 2GB).