Which ram is better for Gaming (no overclocking)

G.SKILL Sniper Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 2133 (PC3 17000)

http://www.newegg.com/Product/Produ...-cables-_-na-_-na&Item=N82E16820231518&cm_sp=

OR

CORSAIR Vengeance 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800)

http://www.newegg.com/Product/Product.aspx?Item=N82E16820233144

For gaming it won't matter one bit. Though you'll have to "overclock" something to get full speed on either of those for some systems.

memory speed only really matters if you're using onboard graphics or are doing something that churns through a metric crapton of memory on an ongoing basis. (aka: not games)

Interestingly the Tech Buyers Guru just examined this question. They should be able to make your decision easier as you can weight the cost benefit difference.

http://techbuyersguru.com/ramspeedgaming.php

As I recommend in every "which memory" thread that I post in:
Crucial Ballistix Sport 1600 1.35V

My Current Mobo/CPU

Intel Core i5-3570K Ivy Bridge Quad-Core 3.4GHz (3.8GHz Turbo) LGA 1155 77W Desktop Processor Intel HD Graphics 4000
http://www.newegg.com/Product/Product.aspx?Item=N82E16819116504

ASUS P8Z77-V LK LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard with UEFI BIOS
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131837


I am currently running 8gb(4x2) of the second ram listed (corsair) but was thinking of buying 16gb (4x4gb) of the gskill and sell the corsair ram.

Sell your current 2x4GB kit, get the 2x8GB Crucial set I mentioned. You're guaranteed the get Micron modules since, well, Crucial = Micron.