A few weeks ago, I was trying to diagnose some slight performance issues (small frequent freezes) I was having while playing games. I found that only 7.93gb of 16gb of memory was usuable. I tried many possible solutions for several hours and none worked. I then went into the bios and found that both of my sticks were detected, however, single channel memory mode was enabled. I was confused as this was previously not the case. I checked the QVL list as I upgraded my cpu a few months back and wanted to see if my ram was no longer compatible as I went from an apu to a non-apu. I couldnt find my kit on the list so I bought a new supported kit, but I have the same issues as before. Each stick shows up as 8gb (no memory is hardware reserved). I only have the issue when both modules are installed.
Specs:
Ryzen 5 2600
Asrock Fatal1ty ab350 gaming-itx/ac
Old ram kit: g.skill ripjaws 2x8gb 3000mhz
new ram: g.skill tridentz rgb 2x8gb 3200mhz
AMD RX580 8gb
Corsair cx650
Sorry if format sucks, I'm writing this on mobile.