the X2 4400+ is marginally faster(2-3%), but the E4300 runs cooler and is much more overclockable. I would go after E4300
They are within a few percentage points of each other(depending on app/benchmark). It's easier to get low-cost mobo's for the AMD(low-priced Intel boards are available too), but high-end boards are similarly priced for both systems. DDR2-800(@ 4-4-4-12 ) is best for the 4400+, whereas DDR2-533 or 667(C2D performance is not so memory dependant) is more than enough for the E4300(depends if O/Cing, and by how much). As already stated, if overclocking, the E4300 is the most sensible choice, as all C2D's can attain 3GHz or more clock-speed with proper components. If you have a brand preference, then pick your favorite...either chip is pretty fast. GLC2D e4300 VS AMD X2 4400+ which performs better?