Okay you want to get a 2 sticks. The 8GB would suffice for you and the motherboard can only support up to 8GB of RAM.
The specs of the RAM should be 1.5V, DDR3 1066 (PC3 8500), 240-pin.
Your 2 links show DDR3 1333. I recommend 1066 because I do not want to mess with overclocking. Your motherboard supports 1333, but you'll need to raise some settings for it.