8GB or 16GB RAM?

I'd go for the 16GB. Some photo/video editing can use up to 12GB of RAM, 8GB and you won't have enough, 16GB and you'll have some left over. With 16gb, you should never have to worry about not having enough......it will be enough to last the lifetime of the laptop more than likely.

You won't see any difference in performance between 1333 and 1600 MHz RAM. Go with what size you think you will need for your applications. 8 GB is probably more than enough.

Oh also, what's the difference between CL9 and CL11? And voltage 1.5v or 1.35v?

Can I put a 1.5 v into a 1.35v RAM slot (and vice versa)?
And Can I put a CL9 RAM into a CL11 RAM slot? (and vice versa)?

Firefighter said:

Oh also, what's the difference between CL9 and CL11? And voltage 1.5v or 1.35v?

Can I put a 1.5 v into a 1.35v RAM slot (and vice versa)?
And Can I put a CL9 RAM into a CL11 RAM slot? (and vice versa)?

CL9/CL11 stands for CAS Latency. CL9 is normal for say 1600MHz, although you can get CL9 in other speeds. As far as 1600MHz goes, CL9 would be normal, CL7 would be found in a higher performance kit, while CL11 would be found in a lower performance set. Motherboard DIMM slots aren't classified into different CAS latencies. For 99% of computers, the most common CL rating for that frequency would be what I would get as you won't likely see the difference in CL7/9/11. As far as I know, the lower the number, the higher performance(in general) the RAM...although higher performance is used loosely because you'll never feel the difference.

As far as voltage....1.5v is the standard for RAM and while some motherboards can handle lower/higher voltage, I would read the manual or look up the specs for the motherboard to make sure. 1.5v I'm sure you'd be safe in using, 1.35(lower) would probably be ok too, but please, check with your motherboard manufacturer first. I personally don't see a reason to buy 1.35v over 1.5v, but that's just my opinion.

Thanks kbrady.

I ended up buying 2 8GB 1600 Mhz CL11 1.5V Sticks.