Actually I have founfd this single core CPU outperforms the dual core version. Strange. For me it works. I run Firefox with 6 to 8 tabs open, iTunes, MS Word, Sunbird and perhaps a few other programs and this system has been rock solid stable.
That's what I mean.... if you have enough power to run all that you need, that's all you need. I have the extra RAM and a upper-end CPU/graphics card because I create/edit/dub video and found the lesser systems I had would lag/freeze up too much, especially when multi-tasking I feel, also, that the 64 bit OS helps in this area, making better use of my hardware.