Can I add 1x4gb to my current 2x2gb

[asterix64]

Can I add 1x4gb to my current 2x2gb. My MB is ASUS M4A88TD-V EVO/USB3
(4 slots of memory) will it slow down?

 

[spawnkiller]

yes but all dimm will work at the slower ram speed and maybe even slower as different module is really dificult to run for a motherboard (also 4 dimm is stronger to get running at full speed) So i suggest to pick a brand new 8gb kit in 2X4gb dimm as anyway it sells for about only 40$ and you can pick some in rebate at 25-30$...