(adsbygoogle = window.adsbygoogle || []).push({}); So I want to buy some more RAM for my PC. Currently I have 4GB in 2 slots, I have another 2 free slots, I want to buy another 4GBx2 and end up with 12GB. Should I? Or just get one more and keep it at 8GB?

8GB is overkill enough, you won't need anymore than 4 for pretty much anything for a while but if you really want to upgrade go for it.

But if you are getting 8, it is best to buy the same RAM and in pairs (2x4) or (4x2) Instead of (2x2 and 4).