Re: Intel Celeron D
They seem to be fast actually and are built on Prescott cores, though they don't have Hyper threading to maximize performance which Extreme Pentium 4's have,
though this does'nt seem to matter as they can still be faster than Athlon 64's in Video encoding at stock speeds (not overclocked), and are very overclockable.
Though if I had to choose between a Celeron D and a Pentium 4, I'd go for the Pentium 4 (Or pentium 4 Extreme Edition if you can for the hyper threading to help with every day tasks) though the Celeron D's come cheaper, and do have quite alot of power in them, especially since you can force them to work a bit harder quite well I've heard.
Hope this helps
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