Dual vs Quad
More cores is newer tech which will usually process faster (because of other improvements) unless the software is a bottleneck. I still think that AMD is the best bang for the buck, quad cores, 8 cores and now 16 cores. I have been using a quad core for the last year with no problems maybe a very long time ago AMD had some issues (10 years or so) but now they just give good value and good speed.