Question RAM detected in BIOS and CPU-X but not in use ?

[Demigirlboss]

Hi y'all. I recently built my first PC after helping a bunch of people build theirs, using used parts. I'm running a Ryzen 5 2600 in an ASRock B450M Pro4 R2.0 motherboard, with two sticks of G.Skill Aegis DDR4-2800 XMP certified RAM. I bought the processor and RAM used, but the RAM does seem to have originally been from the same kit (serial numbers are 20080929071 and 20080929072).

When I check in BIOS, both sticks are showing up as DDR4-2133 running in dual channel mode, and in CPU-X

https://imgur.com/YG6Imeb

it shows two DDR4-2133 sticks as well. However, the system is only able to access 8 gigs of RAM, and Lutris only shows 8 gigs in hardware information. I'm running EndeavourOS Cassini Nova. I've already tried reseating the sticks, but the error persists. Any help is appreciated.

 

[helpstar]

Did you update your OS and Lutris yet?
Eventually a RAM limiter in place by Lutris?

check the memory by running memtest.org usb autoinstaller (bootable USB flash drive)

 

[Demigirlboss]

Did you update your OS and Lutris yet?
Eventually a RAM limiter in place by Lutris?

check the memory by running memtest.org usb autoinstaller (bootable USB flash drive)

OS and Lutris are both fully up to date as of time of writing. RAM isn't detected past 8 gigabytes in anything, including GNOME System Monitor and htop.

Ran Memtest86, and it PASSed with flying colours (or, one flying colour to be precise). However, afterwards, I also tested with single sticks of RAM to see if I could maybe isolate the problem to individual sticks, slots, or channels. The system would power on but then get stuck in a boot loop with no POST with one of the sticks, while it booted up perfectly fine with the other stick. Both were in the same slot. However,

https://imgur.com/a/l3cUKyC

Memtest86 passed both sticks, with XMP profiles enabled, and was detecing them, so I'm reticent to believe that it could've been an entirely dead stick or something along the lines of a corrupted SPD.

Edit: Looking closer, I'm noticing another strange behaviour. Memtest86 also detects two 8 gigabyte sticks, and yet it only shows 8 gigabytes of actual memory in the upper left hand corner.