Question / Help RAM problem

[Dontjudge]

Hello everyone.
I wanted to upgrade my RAM alongside other parts of my pc and i got an issue.
My Mobo is Asus Prime a320m- and i've been using an Kingston HyperX 8 GB DDR4 Cl14 2133mHz (Single stick).
Today i bought an Kingston HyperX 8 GB DDR4 Cl15 2400mHz which just simple does nothing at all for me. It's recognized by PC but it still says that only 7.97GB of my memory is usable. Switching the stick places on mobo can't be done and the newer stick (Cl15 2400mHz) doesn't even start the windows if it's the only stick in the mobo at the given time.
I've already tried the msconfig fix but it didn't work out. Can anyone please help me out?

 

[TechyInAZ]

You bought a different model stick of RAM that is your problem. It is rare to have two different models of RAM work together because they are designed to work at different timings and frequencies, each DIMM in a single PC has to work at identical speeds and timings....

 

[Dontjudge]

You bought a different model stick of RAM that is your problem. It is rare to have two different models of RAM work together because they are designed to work at different timings and frequencies, each DIMM in a single PC has to work at identical speeds and timings....

But why doesn't the 15cl 2400 mHz one work on it's own?

 

[c3r1c3]

Most likely the new stick is either bad, or isn't compatible with your MB. Try updating the BIOS (if you can/a newer one is available), but sans that fixing the issue, I would return the new stick.

 

[Dontjudge]

Yea i actually tried messing in the bios for quite a bit with literally no results and ended up returning the thing, thanks a lot guys!