[Build Help] Choosing the right RAM stick to upgrade my PC!

Hello knights from r/buildapc, we meet again.

I have a single 4gb RAM stick, and I want to buy one more so I have 8GB. However, I can't find the exact model I have, and I was wondering if using another model would have any trouble.
If I buy a new one it'd be the same or higher frequency of course, although different model. I've read that it's kind of risky because it may not run right.
This is the stick I have: KHX1600C9D
This is the one I found at a local store: HX316C10F

I read somewhere that it depends on how your system handles it, so here are my relevant parts:
Mobo: FM2-A85XA-G65
CPU: Athlon X4 750K GPU: Sapphire 7790

Also, any guidelines for troubleshooting this in the future (such as how to tell if two RAM sticks can be run together), will be much appreciated. Thanks friends!