I am allocating and using RAM in the MFC program to use my own PCIE Card.
As a command used when allocating RAM, in Win Registry using RegSetValueEx() API (WinReg.h)
After setting BASEPHYSICALADDRESS, PHYSICALSIZE, BUFFERCOUNT,
I am using truncatememory as much as PHYSICALSIZE.
ex) "bcdedit.exe /set truncatememory 28168814592"
However, although it is a PC of the same brand, RAM is allocated or not according to the Secure Boot mode for each PC.
They are PCs with similar specifications, but for some reason, I inquire whether memory allocation is different depending on the Secure Boot mode.
Please also check whether it is related to the PC HW specification other than Windows.
Below are the PC specifications.
PC1) Memory can be allocated only when Secure boot mode is off
(P520, ThinkStation)
CPU: intel xeon w2145
RAM: 16GB PC4 ECC (single)
GPU: nvdia quadro p2200
Windows10 1909 // 18363.1440
PC2) Memory can be allocated regardless of Secure boot mode
(P520, ThinkStation)
CPU: intel xeon w2123
RAM: 8GB PC4 ECC (single)
GPU: nvdia quadro p400
Windows10 1909 // 18363.1440
In addition, can't memory be allocated in secure boot mode on because of the ECC function of RAM used in the Xeon main board?

