I've heard about the Pentium Ms, Mobile Athlon 64s, and Mobile Athlon XPs

[Rock Hydra]

What about the Pentium 4m? I haven't seen too much rave going about them? What's the deal on those things?

 

[Maximilian]

Two words - They suck.

I think theyre just lower voltage Pentium 4's, apart from that theyre the same as their desktop counterparts. Pentium M should replace them completely IMO.

 

[overst33r]

well the pentium4-m is to the centrino like the athlon xp-m compare to the a64 mobiles

 

[Zap]

Isn't that basically a mobile P4? I have a few. They are okay if you have a motherboard that can run them properly, and if you can get them for cheap. There are three problems associated with running these on desktop boards.

#1 The voltage is 1.3v and some boards don't detect this properly. The result is that either the board boots up with the CPU set at 1.6v or the board does not POST. There is a volt mod that can be done by bending one pin on the CPU (check Karaktu's mobile Celeron thread) and then most boards that don't POST with the CPU will POST now with the CPU running 1.2v.

#2 The core has no heat spreader. Though this makes heat transfer better, this also causes the surface to sit lower in the P4 retension bracket than most heatsinks expect. This causes either the heatsink to not clamp as tight (making heat transfer worse) or in some cases the bottom of the heatsink won't contact the core properly at all. The fix for this is to make some kind of spacer out of metal - copper preferred, but people have succesfully used aluminum and I've personally even used stainless steel.

#3 After the first two obstacles are surmounted, the CPU will boot at a 12x multiplier. Regardless of the rated speed of the CPU, the CPU will be stuck with a 12x multiplier. The reason is that the SpeedStep power savings feature is not implemented in the BIOS and thus the CPU will run in the lower speed. To gain value out of the chip you'll need a motherboard that is capable of running high FSB. for instance, to be able to run 2.4GHz you'll need 200MHz, which isn't a problem with any board that can support Northwood "C" chips. To do above that...

Besides the above, the P4 chips are just Northwoods that are capable of running at low voltages. This makes then worthwhile (if purchased cheap enough) to be used if you want a reasonable performing system that runs near silent at low costs.

 

[stevty2889]

Yep, Zap has it right. The biggest problem with using them is defaulting to the lowest mutiplier which you can't change, but I think it's actualy lower than 12x, not entirely sure though, the one I have is a 1.6ghz and it does not seem to have speed step as it runs at it's normal 16x multiplier...which means you pretty much have to overclock everything else to get them to run at even stock speeds. I had to do the pin mod to mine to get it to boot up properly. It runs fairly cool, but not as cool as my dothan I just got. Netburst is on it's last legs with Cedar Mill and Presler anyway, any future product will be closely related to the pentium-m. Merom looks like it will be coming sooner than expected as well.