You can go to Intel.com and read their description of the Intel Centrino notebooks (using Pentium M processor) and how it stacks up to their own Pentium 4M notebook cpus.
A comparison in overall speed is that a Pentium M will be at least 1.5 -2 times as fast as its Pentium 4M counterpart (so 1.7 735 Dothan) would fall somewhere between those extremes. Use 1.5 to be conservative but acually if falls somewhere in the middle so a 1.7 Dothan Pentium will perform at least at a 2.8-3.0 Pentium 4M level (but Pentium M's do not have hyperthreading).
You get a thinner and lighter notebook , much less heat, much better battery life and an integrated chipset designed for efficient use of wi-fi.
Make sure you buy an Intel 715 Pentium M Dothan cpu or above as the 705 1.5 is the older Banias line with 1/2 the L2 system cache (1mg instead of 2mb) and won't save you more than $50.
You will get only 2 hours in many cases (battery life) on a Pentium 4M notebook but you will get at least 3.5-4 hours battery life using wi-fi on a Pentium M notebook and longer with it turned off.
Hey there,
I was considering buying an Acer 1662, it has a Pentium 4 3.0 Ghz with HT. But then, I saw another Acer, the 1680, but it has a Pentium M 1.5 Ghz (Dothan, I think). What should I get? Will the lower clock speed mean lower performance than the P4? I like playing games but I also have begun developing Flash presentations. If the Pentium M performs better, can someone explain what that means besides longer battery life. Any help would be most appreciated. Thanx!

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