I have some G.Skill Trident 6GB and one 2GB stick just gave out on me! am i able to mix ram? so keep the 4gb and use http://www.overclockers.co.uk/showproduct.php?prodid=MY-084-KS&groupid=701&catid=8&subcat=1392 or http://www.overclockers.co.uk/showproduct.php?prodid=MY-008-PA&groupid=701&catid=8&subcat=1389