Intel and AMD

Cooling problem
Intel has a problem. At high clock speeds, its Pentium 4 Prescott is power hungry beyond belief, while AMD, thanks to its Athlon64 processor, stands by laughing. Who cares about power? You should. The P4's high power consumption leads to a high electricity bill, and the chip puts out enormous amounts of heat, which in turn necessitates large and noisy fans to cool it.
Intel has a secret, though. Did you know that the chipmaker produces a processor that only draws one fifth of the power of a desktop chip? Yes, this is a notebook processor we're talking about. So can this miracle chip be used in a desktop system? Does it pack enough punch for a gaming setup? Indeed, it does! Step back and enjoy as the team here at THG demonstrates.
In this article we to present the ingredients required for such a low-power system, namely the appropriate motherboard and the Pentium M processor. We also offer some advice on the correct graphics configuration. Of course, we'll show you the results of our power-consumption measurements, both for the CPU and the entire system, and demonstrate how remarkably fast the system is by providing some benchmarks.
Depending on the feature set, current PCs draw between 120 and 180 watts - even more in the case of dual-core Pentium D systems. The kicker is that these numbers represent the systems' minimum power consumption when idling! Yes, even when they are doing nothing, modern computers are adding extra digits to the bottom line of your power bill. And once you fire up a game, 300 watts or even more aren't outside the realm of possibility! And even though AMD has slightly less power-hungry processors with its Athlon 64 line, even they are only slightly better, drawing between 120 and 160 watts.
Now, if we compare the performance-to-energy requirements of the previous generation platform to that of today's offerings, it becomes painfully obvious that power hunger has grown much faster than the performance. And this is a trend that has not been seen in other components. Consider that the energy efficiency of power supplies has constantly improved over the past years, and devices such as hard disks, optical drives and RAM require relatively little power compared to core system components.

The Next Generation of Cool:AOpen's 37 Watt Pentium M Desktop PC
For most typical users, the upgraded chipset won't really be of much value. Corporate clients, for example, are only rarely interested in new features, and often prefer cheaper, pared-down versions of chipsets. To them, the cost/benefit ratio is usually the deciding factor. Instead, it is the home users, the multimedia users and the enthusiasts that are drawn to the new features.
Also, Intel has found it hard to showcase the perceived benefit of a well-equipped system based on newer platforms. Of course, no one is disputing that a Pentium 4 660 running at 3.6 GHz with DDR2 memory and a PCI Express graphics card packs more punch than a socket 478 Pentium 4 3.4 GHz with DDR400 memory and AGP. However, the increased performance comes at a hefty price, namely a 30% increase in the system's power consumption.
The lack of applications that would justify the development detailed above is beginning to haunt Intel. Not too long ago, hardware makers could rely on bleeding-edge games to ensure an adequately brief upgrade cycle. However, recent games have increasingly called for more potent graphics cards rather than more feature-rich platforms or faster processors.
It is only natural that as a result, some companies are beginning to rethink the standards that should define a "sensible" PC. Since the majority of users aren't fixated on getting the highest performance, the trend increasingly points to more energy efficient and, consequently, quieter components. A well designed, smart system may be more attractive to the average Joe than one that offers a little more performance at the cost of efficiency.
Intrigued by the ATX and microATX motherboards that AOpen makes based on the energy-efficient Pentium M processor, we decided to build a desktop system based on the i915GMm-HFS (microATX) board. This system has no trouble keeping up with current computers, yet offers significant advantages. For example, it forms the basis for a low-noise system, and draws a mere 37 watts when idle - about a third of what a typical P4 system uses.

Conclusion: A Matter Of Common Sense
With clock speeds that currently range as high as 2.13 GHz, the Dothan-based Pentium M with 2MB L2 cache offers the kind of performance we expect from a modern system. Depending on the application in question, the mobile processor offers performance comparable to a Pentium 4 running between 3 and 3.2 GHz. Using the chip, it is now possible to build a desktop computer with a power draw that stays a good deal below 40 watts with the help of AOpen's i915GMm-HFS. Even when paired with a brawny 3D accelerator card, this system won't exceed the 100 watt mark. Without a doubt, this combination is a very interesting option for always-on computers, as it helps keep the power bill low and doesn't waste energy. Bravo, AOpen!
The Pentium M doesn't do so well in the synthetic applications. However, those don't necessarily mirror performance in real-world scenarios. Indeed, when paired with a GeForce 6800 GT, our Pentium M ran current 3D games such as Doom 3 or Far Cry just as well as a fast Athlon 64 or Pentium 4.
However, when raw number-crunching power is needed, for example when rendering videos and graphics or encoding video and audio files to popular formats such as MPEG2, MP3 and MPEG4, the Pentium M is clearly left in the dust. Unsurprisingly, these fields are dominated by the brawnier Pentium 4 and Athlon 64 processors. For these applications, the higher power consumption of the desktop processors is tolerable, since they actually offer a tangible performance increase in return for their power use.
As a result of the lower signal strength used between the motherboard components and the CPU, mobile chipsets aren't especially suited to overclocking. Users looking to combine the energy efficiency of the Pentium M with high performance from overclocking should keep an eye out for socket 479 with a desktop chipset. We expect to see more of these hybrid boards enter the market over the coming months.

In conclusion, we would say that aside from some of the Athlon 64 processors, the Pentium M is really the most sensible choice if you want to build an x86 machine.