I have installed beta EFI BIOS for my P5Q Deluxe but there is a problem with the memory remap feature. usable system memory shows 7GB on windows even though I have 8. I tried even windows 7 and windows 10 GPT and MBR. It is same in every OS. Maybe a memory table update can fix the problem but I don’t know how to do that. Can anybody help me fix that issue please?
Memory remap feature makes computer to recognize more than 4GB RAM. The memory above 7GB is probably reserved for other devices.
Thank you for your reply. I am still using your bios mod specific for my laptop after 2 years 
So what hardware do you think using it? There was not such an issue with the legacy bios. I found a few other people in other forums facing the same problem with that efi bios. I integrated xeon microcodes and able to flash UEFI bios to such an old motherboard but I have that small problem I need to fix. I would be appreciated if you guided me. HERE are the xeon microcode modded and stock BIOS files of the board (both legacy and efi)
Try adjusting TOLUD ?
Also once you figure this out would be useful if you could try ReBarUEFI on this (with a supported GPU, Polaris works btw), because UEFI systems this old are very rare.
No I didn’t. To be honest, I didn’t even know what TOLUD was. I made a quick research but wasn’t able to find a tutorial. About ReBarUEFI, I don’t think my retro pc’s gtx 750 support it.
There’s no TOLUD control setting both in EFI and Legacy BIOS for P5Q Deluxe.
Do you think there is a way to fix it? Like… modding the EFI?
TOLUD (Top Of Low Usable DRAM) defines the upper limit of RAM located within the lower four gigabytes of the address space.