Windows 10: why is my pc installing only half of the ram from the sticks?

basically my issue is that whenever i install a 8gb ram sticnk into my pc, it only registers as 4gb in installed, and a 4gb stick says 2gb installed, so half of what it actually is. im running on an 64 operating system and when i insert both of the sticks it shows up as 6 together. any way i could fix that?

:)

 

Windows 10 only using half the installed RAM

Device name DESKTOP-AJD2UQS
Processor AMD Ryzen 7 1800X Eight-Core Processor 4.10 GHz
Installed RAM 64.0 GB (31.9 GB usable)
Device ID
Product ID
System type 64-bit operating system, x64-based processor

Edition Windows 10 Pro
Version 20H2
Installed on ‎2021-‎03-‎15
OS build 19042.631
Experience Windows Feature Experience Pack 120.2212.31.0


My problem is in bold. Windows and the programs in windows can't use all RAM.
I had an older installation of windows 10, version 1909 and it has the same issues as this new install from MS download to a formatted USB drive build version 20H2 on a new SSD.
BIOS shows all 4 sticks of RAM and currently set to XMP profile 1. I've used different BIOS versions and RAM configuration settings with no change, except faster or slower performance.
I've used memtest86 full test (which took ~14 hours to complete!) and zero errors on all 4 sticks of RAM.
CPU-Z detects all RAM with the only difference being two were mfg. 1 week earlier than the other two.
I found some other answers on this and other forums and tried their suggestions to no avail, which include:
The MSConfig -> Boot -> Advanced -> Maximum Memory check box
I've also put all 4 sticks into a gigabyte B550 Aorus Pro with an AMD 3700x with the same result, so it's not the processor, board, or BIOS.
The current system is:
Gigabyte AX-370-Gaming K7 BIOS F4
AMD Ryzen 1800X












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Another post in this forum asked for someone with a similar problem to show a CMD WMIC query.

 

Half of RAM 'Hardware Reserved'

I have 32GB of RAM installed and half is "hardware reserved" by Windows. I've tried every suggestion I can find, including moving the modules around to different slots. My MB does not have onboard graphics. Specs:

• Motherboard: Gigabyte GA-AX370M-DS3H (BIOS on latest firmware)
• CPU: Ryzen 7 2700X (upgraded from 1700x and it didn't help)
• RAM: Corsair VENGEANCE® LPX 32GB (2 x 16GB) DDR4 DRAM 2400MHz C16 Memory Kit
• GPU: Nvidia RTX-2060 Super

The BIOS, Windows, CPUZ and HWInfo all show 32GB installed and both slots used, but Windows says "Hardware Reserved: 16.1GB". This was occurring on Windows 10. I am currently running Windows 11 (beta channel) and it didn't help. I also upgraded my CPU from a Ryzen 7 1700 with no change. Pics: Imgur: The magic of the Internet

 

pc crashing with two ram sticks .

I have just tested my pc with individual ram sticks and it is crashing only with one particular ram stick, ill rma that and see if the issue still occurs,

Thank you for the help.