Overclocking the Pentium M: A Silent Powerhouse

Overclocking/Overclocking Tests by Agent2 @ 2005-01-21

One of Intel?s latest CPU runs at 1.6ghz, no there is no typo here, the Pentium M normally intended for laptops have been given a chance to shine in desktop systems also with the help of resourceful motherboard manufactures. We take a closer look at DFI?s offering to see how far we can overclock this new "Dothan" CPU.

  • next


Intro by the editor

Back in the days of the AMD Thunderbird and Intel Pentium 3 both CPU's were quite evenly matched. When the time came to push forward AMD stuck with their design of many operations per cycle, while Intel had problems running the P3 at speeds higher than 1ghz. In order to resolve that issue they started on a new design, the P4, by making the pipelines longer in the CPU the Mhz of the chip could be scaled higher then the P3, however less operations were performed per cycle, and so the "Megahertz Myth" was born.

Where as before more Mhz meant a faster CPU, this was no longer true with the P4, the first incarnations came clocked at 1.4-1.5Ghz and were quite the underperformers, hampered by a 400Mhz FSB these CPU's had trouble keeping up with lower clocked P3's and AMD Tbird's. But once Intel started ramping up the P4's speed it scaled higher then the competition and was soon combined with a 533Mhz and 800Mhz FSB which gave the P4 quite a bandwidth boost and upped performance to unseen levels.

AMD had trouble keeping up with their AMD Athlon XP, the successor of the Tbird, and soon it was the P4 running at clock speeds almost double those of the Athlon XP which took first place in all benchmarks.

Then the new Athlon 64 roared its head, capable of even more operations per cycle compared to the Athlon XP, it looked promising right from the start. Now AMD has their A64 running at speeds ranging from 1.8 to 2.6Ghz and this leads to excellent performance. Intel on the other hand with their P4, which scaled very good in the beginning, has run into a thermal wall, the current crop of Pentium 4 processor are producing more heat per square centimeter then a the core of nuclear reactor. Stranded at 3.8Ghz the P4 is no longer king of the hill.

Now if you think AMD has won the game, think again, they have problems scaling the A64 too, and it won't be too long before they run into wall also, stopping the Megahertz increase.

The solution both CPU makers have come up with is: Dual Core. As you might have guessed, it's basically 2 cores on a single CPU, in a single CPU socket. Each one taking up a part of the calculation jobs which need to be done. However, for the OS, this setup will appear just like any other multiprocessor system. While these MP systems provide without a doubt a smoother PC experience, they tend to be as fast as single CPU system when it comes to gaming or single task operations. Unless all software is rewritten for dual CPU setups, you won't see much gain in today's applications or games.

So while Dual Core seems to be the future for AMD and Intel feature wise, the enthusiasts and speed hungry gamers are pretty much left in the cold. Speaking of cold, the only way current P4 and A64 can scale far beyond retail speeds is through ice-cold cooling (VapoChill/MachII); but these are options only a few of us can afford.

So where lies the future for the overclocking enthusiast? Well maybe in laptops. Or to be more precise, Intel's CPU's used in laptop. Their Centrino line is currently powered by a version of their Pentium which has been tagged with an M, the Pentium M. The M, of course, stands for Madshrimps, or maybe Mobile, nobody really knows ;).

The Pentium M comes clocked at speeds ranging up to 2.1Ghz but seem to perform equally good as a Pentium 4 running at 3Ghz+. Much like the A64 it does more operations per clock cycle then the P4.

Intel does not want this Pentium M to be used in desktop PC's so you won't see a Dell or HP tower with an "M" tag any time soon. Third party motherboard manufacturers however have taken it upon themselves to give the enthusiast a possibility to run these laptops CPU in desktop motherboards.

Today we have a featured review of one of these "Little Mean Gaming Machines" submitted by avid forum member agent #2

So let's read on to find out exactly how to set up and overclock one of these Pentium M powered machines.
  • next