Intel Celeron - I beleive the mobile celeron is based on the P3-m core and the new P4-m core, albeit at reduced L2 cache, and lower performance. At all costs, stay away from a Celeron based notebook. They are horrible. Horrible. Horrible. - did i mention that they are not very good and should be kept away from?
Intel Pentium 4-m - First off, make sure that the notebook that you are looking for is in fact a P4-m and not a standard P4 as many notebook manufacturers put in there laptops. The P4-m is identical to the desktop P4, except that it has Enhanced SpeedStep enabled on the core, and runs at lower clock speeds. The CPUs are more expensive as they are specifically chosen out of a group of P4 processors, because of their slightly lower thermal properties, and lower power consumption due to a possibly slightly higher manufacturing process (It is just chance really). The P4-m has 512KB of L2 cache, and runs at speeds of up to 3GHz now, although the faster the P4-m, the higher the power consumption. On battery, the P4-m reverts to a clock speed of 1.2GHz (SpeedStep) unless you require full power, and then you can configure it to retain its Full clock speed. It is not designed as a mobile processor, so it is not IDEAL. It runs quite hot, and guzzles a bit of power. The Pentium4-m has a maximum gate junction temperature of 135'C, in which case the chip will explode or something
- I'm not sure, i don't think anyone has ever got it that high. It will infact reduce clock speed at any temperature over 100'C using the famous Pentium 4 Clock throttling, as it approaches 120'C it will induce CPU wait states (much like those used on early Pentium (1) notebooks) and if the temperature continues to rise, the CPU will simply shut off. However, most notebook manufacturers program their computers to cut once 85'C or so is reached, to avoid the nasty smell of bunring plastic or something worse I assume.
Intel Pentium-M - By far the best notebook CPU available today in my opinion. Codenamed "banias" and the CPU used in a Centrino configuration, it has 1MB of L2 cache, which switches on and off in bits as it is needed to lower power consumption. It has a maximum clock speed of the moment of 1.7GHz, and clocks down in a multitude of different steps on battery. e.g. a 1.6GHz Pentium -M on battery will run at 600MHz Deeper Sleep (i.e. uses very very low voltage (0.956V)) when it is not processing anything. If it needs to process, it will come out of Deeper Sleep, and run at a higher voltage but still 600MHz, if the thread requires more processing power, it will move up to 800MHz; 1000MHz; 1200MHz; 1400MHz and finally to 1600MHz as the processor is needed. it can swap these speeds almost instantly and they greatly increase battery life (for instance, the Dell Inspiron 8500 and the Dell Latitude D800 are almost identical notebooks, one with the P4-m, one with the P-M. The 8500 runs for about 3hrs on battery, the D800 for about 4.5 when used nominally). The D800 will clock down to 1.4GHz if the Core temperature exceeds 85'C and if it continues to rise, will slow down to 600MHz, if the temperature rises beyond this, it will presumably act in a similar fassion to the Pentium 4-m. However, I might add, because the Pentium-M runs at 1.7GHz, but does more instructions per clock cycle (- and thus performs like a P4 2.6GHz), it runs very cool. I used my D800 in class today, and since it was just for note taking this particular lesson, the temperature did not exceed 30'C, and the fan didn't come on once (although the outside temperature was only 23'C itself - It's winter here).
The performance is superb, the power consumption is incredibly low, and the heat generated is marginal, it is the best high powered mobile CPU you can buy.
AMD Mobile AthlonXP-M
I beleive the AthlonXP-M only goes up to 1800+, but this is ofcourse comparing it to a Pentium4. So it would perform like a 1.8/1.9GHz P4 on average. The clock speed is thus 1.5GHz at full, and 533MHz at its PowerNow! Powersaving technique's minimum level. It operates on a very similar principle as the Pentium-M, and clocks from 533MHz to 1000MHz; 1133MHz; 1266MHz and 1500MHz (at its max clock speed, it only uses 1.25V vs the P-M's 1.484V at Max Clock). It is not plagued by thermal problems that trailed the Athlon Thunderbird, but it does not have as flexible a solution as Intel - however, it must be considered that notebooks these days rarely reach those high temperatures. The AMD mobile solution, is also very much cheaper than the Pentium-M. At 1.5GHz, the AMD is 1/5 of the price, and the performance is only marginally lower.
TransMeta's Crusoe is a nice CPU to consider, but only if you are looking for ULTRA portablility and mediocre performance (not suitable for 3D games and graphics).
I will always use an AMD in a desktop system, because in my experience, they are more cost-effective, reliable and perform higher - they also have longer life spans and are more fun to play with, but in notebooks it is a different story. There is just not enough chipset support for the AthlonXP-M to be as serious contender - especially where gaming is required. The AMD 64-buit solution (whatever they decide to name it) will be excellent, and unrivalled for a period in time, as it will have the chipset support, the 3D Graphics support (chipset dependant) and 64-bit computing.
I can't wait.
Anytime,
RaPTuRe
Who's General Failure and why's he reading my disk?
Facebook
Twitter
Instagram