Check out some benchmarks. I dont know much about Intels, but as far as i know, with their chips, the higher clock speeds the faster(not how AMDs are). And since the P4 has HT and is at a higher clock speed id guees the P4 w/ hyper.
Although AMDs have a superior architecture. If youre familier with how they work then you understand why the clock speed dosent exactly matter with the over all performance of the cpu. Although I dont know anything about the pentium Ds.
Dual cores are good for multi taskeing, because it has two cores. You could think of it as two cpus in one, although again, im not familier with the new pentiums, im assuming it works the same way or close to AMDs.
If youre getting a CPU for gameing, I highly suggest looking at AMDs. Im not an AMD "fan boy". Just AMDs are known for being better with gameing and Intels with hyper threading are better for video editing and whatnot.
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