16gb only 7.95 usuable & underclocking issues

[Guest]

Bios only show 8192mb when I have 2133mmhz 2x8gb Ram in my PC. The system shows 16gb (7.95 usuable) and cpu-z shows me 16gb in dual channel.
At first I thought it was a faulty RAM stick so I rma'd the stick and found out it still worked. (They tested on Intel system) They sent it back and I thought one of my cpu pins have been bent or cpu fan was too tight but that wasn't the case either. I underclocked my RAM from 2133Mhz to 1866mhz and it showed full 16gb in the bios as well as in windows 10 and everything seemed fine. But now my system was unstable and I would get a bsod every few minutes.

suggestions on how to fix usuable ram? or underclocking issues ( I don't mind if my ram underperforms slightly.)

Specs:
AMD ryzen 5 1600 OC 4.00ghz
Gtx 1050ti FOC
2x 1x8gb 2133mhz corsair value select
Msi b350 PC mate
thermaltake 500watt 80plus PSU
1tb seagate barrucuda HDD

 

[PrivilegeYT]

First step I can advise you is to make sure that you aren't on Windows 32-BIT and you are on Windows 64-BIT

Find out BIT Version : https://support.microsoft.com/en-us/help/13443/windows-which-operating-system

 

[RememberThe5th]

Load default update the bios, load def again, select correct ram voltage and timings manually that are provided on sticker and see if it works, did you use XMP? Sometimes xmp can do that.

 

[Guest]

I figured it out! I lowered the frequency to 1600mhz and all is working fine now. 16gb is up and running

 

[RememberThe5th]

That is weird. The ram should work at its rated frequency unless you have unstable OC.
Also to add Ryzen Benefits from SPEED or ram.

 

[Guest]

That is weird. The ram should work at its rated frequency unless you have unstable OC.
Also to add Ryzen Benefits from SPEED or ram.

Thats true but I guess 1600mhz will do. I bet its the motherboard's fault but I can't be bothered dissembling my whole computer and shipping it cross states for rma.

 

[RememberThe5th]

Hmm, Did you tried to put one ram, set to its frequency, save it, then shutdown, put another ram and check?
Usually this worked for me.
Yes I have same issue as yours, but with ram detection.