dual core is fine if the software can handle it. I had a fast AMD single core at 4200 then got a core2duo Intel and was surprised to find each core at 1800. When single tasking it was very much slower than the AMD. When multi tasking it was quicker. Look at the mobo spec you are thinking of buying and then enter that info into the crucial.com/uk site it will tell you what memory can be used with it. You can then choose the fastest that you can afford.