Hi guys , ive got 2 lots of adata ddr400 512mb sticks of RAM (16 chips double sided) to give my system a 1gb of RAM total . These chips have a CAS of 2.5 . My problem is i want to upgrade with another 512 stick of ram but they dont make the adata 512 stick that i have any more . The 2 closest matches are a adata 512 ddr 400 with a CAS of 2.5 but it has only 8 chips (single sided) or a adata 512 ddr 400 with 16 chips (double sided) but this has a CAS of 3.0 unlike my currents setup which has 2.5 . Im hoping someone with RAM experience can tell me the best one to buy . Do i go for the same CAS of 2.5 but the strip is single sided as opposed to my double sided or do i go for the 16 chips double sided but has a different CAS of 3.0 compared with my existing strips of 2.5 . Many thanks RAM guru`s . Cheers , Steve