Mobile Pentium 4 on an 850E Chipset

[qliveur]

Hi, all.

I've been playing around with my folks' old Dell Dimension 8200, and discovered that it's one of the later ones with an 850E chipset that supports 533FSB. I updated the BIOS to the one accidentally released by Dell that supports hyperthreading, and with the parts as cheap as they are for it, I decided to upgrade the CPU as much as possible; well, on the cheap, at least. I'm basically just playing around.

Normally this would mean a Northwood 3.06GHz/533MHz FSB, but I noticed that a year or so later Intel launched these Mobile Pentium 4 HT's for Socket 478, like this one, that have a higher clockspeed but still run on a 533MHz FSB. Their TDP and voltages are very similar to their desktop counterparts.

Would one work with an 850E desktop motherboard? I know that it sounds crazy, but I figured that it wouldn't hurt to ask.

 

[waffleironhead]

I wonder what the voltage requirements of the cpu is compared to what the socket will provide.

EDIT: looks like you have that covered...

 

[HannibalX]

IIRC it won't work because the CPU is actually 479 pins. This is why the Core Duos and Pentium Ms couldn't be used in desktop S478 boards.

 

[imported_Lothar]

Originally posted by: iFX
IIRC it won't work because the CPU is actually 479 pins. This is why the Core Duos and Pentium Ms couldn't be used in desktop S478 boards.

This.

 

[waffleironhead]

Originally posted by: Lothar

Originally posted by: iFX
IIRC it won't work because the CPU is actually 479 pins. This is why the Core Duos and Pentium Ms couldn't be used in desktop S478 boards.

This.

you guys are thinking the pentium M which is indeed the s479, while this is the p4m, a whole different chip.

 

[HannibalX]

Even though they are different architectures I believe they are also 479 pin.

 

[imported_Lothar]

Originally posted by: waffleironhead

Originally posted by: Lothar

Originally posted by: iFX
IIRC it won't work because the CPU is actually 479 pins. This is why the Core Duos and Pentium Ms couldn't be used in desktop S478 boards.

This.

you guys are thinking the pentium M which is indeed the s479, while this is the p4m, a whole different chip.

Good catch.
Now that I think about it, I do recall my pharmacy school laptop warming my legs...It was a Pentuim 4(not a Prescott).
My LCD screen hasn't worked the past 2 years so it's in some corner under my bed.

 

[waffleironhead]

Originally posted by: iFX
Even though they are different architectures I believe they are also 479 pin.

http://www.cpu-world.com/Socke...%20%28mPGA478B%29.html

 

[HannibalX]

Originally posted by: waffleironhead

Originally posted by: iFX
Even though they are different architectures I believe they are also 479 pin.

http://www.cpu-world.com/Socke...%20%28mPGA478B%29.html

Thanks for the generic S478 info. I'm sure it's really helpful to someone.

So, lets see you drop a Mobile P4 into a desktop S478 board, that is what this thread is about. Lets see you do it and see it work. I'd love to see it done.

 

[waffleironhead]

Originally posted by: iFX

Originally posted by: waffleironhead

Originally posted by: iFX
Even though they are different architectures I believe they are also 479 pin.

http://www.cpu-world.com/Socke...%20%28mPGA478B%29.html

Thanks for the generic S478 info. I'm sure it's really helpful to someone.

So, lets see you drop a Mobile P4 into a desktop S478 board, that is what this thread is about. Lets see you do it and see it work. I'd love to see it done.

You are the one going on about it actually being a 479, if you'd bother to read the link you would see that there were actually mobile p4 in the 478 package.

 

[HannibalX]

Originally posted by: waffleironhead

Originally posted by: iFX

Originally posted by: waffleironhead

Originally posted by: iFX
Even though they are different architectures I believe they are also 479 pin.

http://www.cpu-world.com/Socke...%20%28mPGA478B%29.html

Thanks for the generic S478 info. I'm sure it's really helpful to someone.

So, lets see you drop a Mobile P4 into a desktop S478 board, that is what this thread is about. Lets see you do it and see it work. I'd love to see it done.

You are the one going on about it actually being a 479, if you'd bother to read the link you would see that there were actually mobile p4 in the 478 package.

Have I disputed your information?

Lets see it work. Post it when you got it working.

 

[VirtualLarry]

Originally posted by: iFX
So, lets see you drop a Mobile P4 into a desktop S478 board, that is what this thread is about. Lets see you do it and see it work. I'd love to see it done.

I've done it. It works. I used an 845 chipset (854P, 845E, I don't recall the suffix). It was on a QDI board that supported overclocking, and a 400, 533, and 800 FSB.

It was a Mobile P4 2.0 Ghz. The problem with running the mobile chips in a desktop board (if they even boot at all, which is definately not guaranteed, most wont), is that they support SpeedStep. SpeedStep is used to switch between a low (12x multi) and a high (20x multi) speed. But the chip defaults to low (12x multi). So without speedstep, your chip is going to run at 1.2Ghz @ 400FSB. Not very fast. Thankfully, I could overclock the FSB to 800 with jumpers, so the chip ended up running at 2.4Ghz.

Edit: Oh yes, one more thing. The mobile P4 chips lack a heatspreader, so you have to be careful as to what heatsinks you use. The stock OEM Intel heatsink does work for this, so if you have one handy, use it.

Edit: The same mobile P4 CPU would NOT boot in an Asus/HP OEM 865G mobo. I am unaware of any 865 chipset boards that will boot a Mobile S478 P4.

link

 

[Soulkeeper]

My 1.8 P4M worked flawless in my abit ic7/ic7-max3 boards
depends on the motherboard/bios

 

[xylem]

Mobile P4-based socket 478 chips can operate in some desktop boards. Here is an old AT thread detailing Mobile Celeron (S478) overclocking in desktop boards, which also includes a bit of information about experiences with P4M overclocking. I used one of the combos which is described in that thread, and the machine is still in operation at a friend's house.