Can anyone explain to me the difference between a 400MHz 184Pin 512MB PC3200 DDR RAM DIMM 2.5V which is 2.7Gb/Sec and one that is 3.2Gb/Sec. I'm buying a barebones system from Novatech.co.uk and but I need more RAM for it, 512 to add to the 256 that comes with it. Barebones https://www.novatech.co.uk/novatech/specpage.html?BB-NF430 RAM https://www.novatech.co.uk/novatech/products/a540x1y0z1p0s0n0m0 They sell several types of the 512 RAM, one states that it is "For Novatech Systems" and is 2.7Gb/Sec but the other two are 3.2Gb/Sec. I suppose the first must be the one I want, I've been trying to make sure but their phone and email support is no good at all so I havn't been able to speak to anyone. I'm also curious whether it will be OK to mix a 256 stick with 512 but I realise you may not be able to answer that because it depends on the ram or motherboard (Foxconn/Winfast NF4UK8AA-8EKRS) Ok thanks for any insight, i would wait and try get in touch with them but I need to order it soon really. Thanks again.

Alright I've sorted it out now i think, finally got them on the phone and they said to get the 3.2Gb/Sec and that DDR RAM can be mixed sizes. Thanks anyway, hopefully someone wondering the same might find this.

DDR-SDRAM model numbers correspond to the amount of bandwidth they can handle. PC3200 can handle 3.2GB/sec, PC2700 can handle 2.7GB/sec, etc. If you mix the two, both sticks will run at the bandwidth of the lower of the two. In other words, if you pair up PC2700 & PC3200, they will run at 2.7GB/sec http://www.kingston.com/support/faqs/memory/general_6.asp ASUS A7N8X-X Athlon XP 1800+ 8.5 x 200MHz 1280MB PC3200 2.5-3-3-7 Asus A9550GE/TD 128MB WinME/WinXP Pro SP1