I have Windows 10 enterprise and I installed 32 gb ram in my board and for some reason hardware reserved is taking up 103 mb. I do not have onboard graphics I have a dedicated gpu there is no onboard on my motherboard. It's not a big issue but just annoying it doesn't show just 32 gb installed. It's an Asus aura 970 using a amd fx 8350 8 core. The ram is g skill ddr3 1833 MHz.
I've found that Windows will take a bit of RAM regardless of what an Add-in card has. I have an AMD Radeon HD 6670 1GB Add-in PCIe 16X adapter on my WIn10 computer with 8GB RAM, DXDIAG Display tab shows it has 4848MB memory available.
It's weird because I have another pc with a gigabyte board that has an amd six core cpu and 16 gb ram and dedicated graphics and all 16 gb shows up no usable crap.
I have read on the Asus Rog forums and at Overclock.net in the Asus forum that some of there boards don't display the full Ram as you are seeing , and it is also what I see on my new X99A II (31.9GB, 88.9mb hardware reserved) , however RamMon shows all 32GB . I have yet to see a full explanation of this though, ie exactly what is reserving it..
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