It's probably better to go for 2x2GB.That way you make use of the dual channel technology. Some of the best brands are Corsair, G.Skill and OCZ.Kingston is also well known but some people don't like their products
I will be going for a Biostar TZ77XE3 LGA 1155 Intel Z77 motherboard or the ASRock Z68 Extreme3 Gen3 LGA 1155 Intel Z68 HDMI SATA 6GB/S USB 3.0 ATX Intel Motherboard. Now which model from which brand should I buy my RAM from?????