Pentium M Dothan 400FSB possible upgrade?

[3dfxManiacz]

I have a toshiba R100 laptop with 1.1Ghz Dothan 400FSB, issit possible for me to get 1.7Dothan 400fsb on ebay n plug it in? will the bios be able to detect extra 600mhz?

 

[nvalhalla]

If the pinout is the same and the voltage is the same it could. Laptops often have the CPU soldered on to prevent people from buying cheaper processors and upgrading it themselves instead of paying the premium for the upgrade from the company. Did they sell that exact model of laptop with that CPU? If not the BIOS probably won't recognize it.

 

[sijo45]

The Portege R100 is a sub notebook and as such the processor used (Ultra Low Voltage) has a peak power usage of 5watts. Therefore, the cooling system in the body is minimal to say the least (I am not even sure it has active cooling). If you put a 1.7GHz processor in it, even if it worked, at best the battery life would go through the floor and at worst, it would overheat quicker than you can say "Oh, my lap is getting quite warm!"

 

[joefriday]

not to mention, the far majority of the ULV CPUs were ball grid array, being soldered onto the motherboard.

 

[sijo45]

That would make sense actually! Given the space premium, wasting height with a socket (and a couple of grams) with a socket would seem an odd thing to do.

 

[MU_Engineer]

not to mention, the far majority of the ULV CPUs were ball grid array, being soldered onto the motherboard.

From what I've seen, ALL of the Core and Core 2 LV and ULV chips are BGA and most of the standard-voltage chips are socketed. I believe that it is to reduct notebook thickness. The socket adds roughly 3/16" to the height of the CPU-heatsink setup and when you're dealing with a small notebook that is generally 1.0-1.1 inch thick *including the screen thickness* that 3/16" is awfully expensive.

There would be no other good reason to use a BGA setup because it limits the interchangeability of parts as the CPU is soldered to the board. If the manufacturer guesses the demand of the 1.06 GHz vs. 1.20 GHz parts wrong, then they're stuck with motherboards that can't be used. If the CPUs were socketed, then at least they could use the re-motherboard with the different-speed CPU and only be stuck with a CPU, not a CPU and motherboard.

You can replace a BGA processor, but it requires a $2000+ vacuum desoldering rig and a whole lot of patience. You'll need to desolder 479 balls and then resolder them with the new chip. You won't be able to use the 1.7 Dothan because your computer is only rated for the 5 watts that the low-voltage units dissipate and draw. The Dothan chipsets are unusable for the Core/Core 2 LV/ULV chips, so you're stuck with your Dothan.