Mixing Memory?

[shipinabottle]

Hey Guys/Girls

I've been out of the game too long and my memory (Pun!) is failing me.

The pc i'm looking to upgrade the mmeory in currently has 4gb of this installed:

http://www.ocztechnology.com/ocz-ddr3-pc3-12800-gold-low-voltage-dual-channel.html

I'm wondering if i could just add a different brand from the same tier without problems? such as

GeIL Black Dragon 8GB (2x4GB) DDR3 PC3-10666C9 1333MHz Dual Channel Kit (GD38GB1333C9DC)

Thanks for the replies in advance

 

[shipinabottle]

Cheers peeps.

What would you recommend I do? start fresh with a different brand?