RAM 800mhz or 1600mhz for Android Studio

[Haider Akbar]

I have HP 15-R004ne.
Processor: Intel Core i5-4210U @ 1.7GHz (4 CPU), ~2.4GHz
RAM: 4GB (800MHz)

I want to extend it, so I need a suggestion. I should buy 8GB 800MHz or 1600MHz?

 

[codesplice]

http://support.hp.com/us-en/document/c04328092

So I'd go for 1600MHz