Re: Whats better?
Clock speed isn't really everything these days. The Dual core is nice, but the Quad has two more processing cores and a better graphics processor. The 'Clock speed' is just the 'speed' of each core (in herts, or cycles per second) multiplied by the 'core multiplier'. Alot of Pentium 4s could hit 3GHZ, but they had very little cache and were only single core.
Generally speaking, More cores is 'better' for high performance - 4 cores at 2.9 is better than 2 cores at 3.4 generally speaking.
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