Question about P4 vs Pentium 4 Mobile

[Inverted]

I have a mini-itx mobo that says it supports P4 and Pentium 4 Mobile chips, socket 478, up to 3.06ghz. Is there a benefit in speed with going with one vs the other? I know the pentium 4 mobile runs 12W cooler, but that isn't much of a concern to me.

Update: This is the board that I am using. It states that it supports P4's up to 512k of cache, any reason why it wouldn't support the 1M version of the 3.06ghz P4?

TIA,
Inverted

 

[stevty2889]

The 3.06 desktop chip has hyperthreading, not sure if the mobile one does or not. Other than that, there should be no differance.

 

[pkrush]

Looks like it only supports up to the 533fsb Pentium 4's, and that will mean your fastest choice will be the Northwood 3.06 with Hyperthreading (since the 845 chipset never supported Prescotts). Mobile CPU's may run on that board properly, or they may default to the lowest multiplier and run at 1.2 ghz instead and there's really no way to tell which "Supports Pentium 4 Mobile CPU's" means.

 

[stevty2889]

Looks like there is a differnt version of the board that supports the mobile pentium 4's, whats the exact model number, since it's showing 3 differant version on the page you linked too. Definatly won't support 1mb cache chips, I don't think they even made a 3.06 prescott with HT, and prescotts are space heaters and power hogs anyway, not to mention slower clock for clock at those speeds.. The 3.06ghz northwood is definatly the best chip to use with that motherboard. Unless you have the exact model thats supports mobile P4's, a mobile P4 will default to the lowest multiplier, won't run at full speed, and you won't be able the change the multiplier, so I would get the desktop version to be safe.

 

[Inverted]

I do have the MB850MF(version that supports mobile chips)

What would be the reason that it wouldn't support one of the 3.06ghz Mobile HT 1mb versions? Why would it support up to 512k, but not the 1mb?

Looking in the motherboard manual it appears the mobile chip will run at 4 x 100mhz instead of 533, yet the desktop chip can run at 400mhz or 533mhz, why would this be? Is this correct or do you think if I put a 3.06ghz HT 533 mobile chip in there it will work?

Update: I just spoke with a rep at the company, he wasn't totally sure, but he thought the 1mb version should work fine.

How would a Pentium 4-M 2.2ghz compare to the 3.06ghz in performance?

 

[stevty2889]

Originally posted by: Inverted
I do have the MB850MF(version that supports mobile chips)

What would be the reason that it wouldn't support one of the 3.06ghz Mobile HT 1mb versions? Why would it support up to 512k, but not the 1mb?

Looking in the motherboard manual it appears the mobile chip will run at 4 x 100mhz instead of 533, yet the desktop chip can run at 400mhz or 533mhz, why would this be? Is this correct or do you think if I put a 3.06ghz HT 533 mobile chip in there it will work?

Update: I just spoke with a rep at the company, he wasn't totally sure, but he thought the 1mb version should work fine.

How would a Pentium 4-M 2.2ghz compare to the 3.06ghz in performance?

The 1mb cores are Prescott based..the motherboards not designed to handle the power requierments of prescott, so it won't work.

If the mobile chip is running at 4x100..it's running at 400mhz, really really really slow in other words..but that doesn't sound right, since the lowest multiplier is normaly 6x, so it would run at 600mhz, still very slow.

A 2.2ghz P4-M will be a good bit slower than a 3.06ghz, especialy the desktop version since it has hyperthreading.

 

[Inverted]

Looking here

It shows the Northwood 3.06ghz HT desktop cpu to use 81.8W and the mobile P4 HT Prescott 3.06ghz to use a max of 88W. That is only a difference of ~6W....?

 

[stevty2889]

Originally posted by: Inverted
Looking here

It shows the Northwood 3.06ghz HT desktop cpu to use 81.8W and the mobile P4 HT Prescott 3.06ghz to use a max of 88W. That is only a difference of ~6W....?

Prescott and nothwood use differant voltages..the voltage regulator on the motherboard is designed for northwood, not for prescott..feel free to try anyway, but I tried once and fried the motherboard and power supply..if the board doesn't support it..the board doesn't support it.

 

[Inverted]

I am going to check the bios and see if there is a way to specify the voltage for the cpu. The Northwood actually uses a higher voltage.

Pentium 4 HT 3.06 3066 MHz 512 KiB 533 MT/s 23x 1.475/1.55 V 81.8 W Socket 478 November 14, 2002 RK80532PE083512


Mobile Pentium 4 HT 532 3066 MHz 1024 KiB 533 MT/s 23x 1.15/1.4 V 50/88 W Socket 478 June 2004 RK80546HE0831M

and it also supports this chip:

Pentium 4-M 2.2 2200 MHz 512 KiB 400 MT/s 22x 1.2/1.3 V 20.8/35 W Socket 478 September 16, 2002 RH80532GC049512

 

[stevty2889]

It's your choice, but don't say I didn't warn you. There is a possibility it will work, but just as much possibiity it may blow your motherboard. And if you are doing all for the cache..keep in mind that while prescott has more cache, the cache is slower on Prescott.