Recommend a memory upgrade!

[bazzabear]

I have an Asus P8Z68-V motherboard, stating that it is compatible with up to DDR3 2133.

Currently it has all 4 slots filled with 2BG 1600MHz Kingston Blu sticks.

What's my best option to upgrade?

Buy 2x8GB sticks? Is there any value in retaining 2 of the 2GB so I have 20GB in total? Would that mean that I have to stick to 1600MHz, and would I therefore be better off ditching all of the 2GB sticks and going with a faster memory speed?

As you can see, I have a lot of questions! Please help!

 

[bazzabear]

Gaming.

I wondered whether going to 16GB might see transition improvements in games like GTAV, CivV which have long load times. Or is that entirely down to drive speed?