Pentium M vs Pentium 4-M

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movax

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H'okay! So, the Pentium M, whilst crazy-old by our standards now, was proven to beat the Netburst core P4s and such.

Other issues aside, such as looks, weight, portability, etc, I have two laptops sitting in front of me. One is a Pentium 4-M 2.2, 512 RAM, the other is a Pentium M, 1.4GHz, 512 RAM as well.

I'm trying to decide which one to keep/sell. Can the Pentium M's rather low clock-speed be covered by its efficiency? It's a Dell Latitude D600, btw (the other is a Dell Latitude C640).

The deciding factors will be whether the 1GB SO-DIMMs I bought will function in the P-M notebook, and I guess if someone could confirm that I could toss in a higher-clocked Pentium M in the future. (I think the 1.8, 2.0GHz models are ~$100 now?)

*EDIT* They are both mobile versions.
 
The Pentium M is the way to go. It runs cooler and draws less powerful, and is comparable, if not superior to the Pentium 4 M.
 
That's what I figured, thanks guys. I feel sad parting with my C640 though, now. :(

How many cores of Pentium Ms were there? The terms Banias & Dothan come to mind. Anyone can explain?
 
movax said:
That's what I figured, thanks guys. I feel sad parting with my C640 though, now. :(

How many cores of Pentium Ms were there? The terms Banias & Dothan come to mind. Anyone can explain?
Click to expand...

Banias:
400MHz FSB
1MB L2
77 Million Transistors
130nm

Dothan:
400MHz/533MHz FSB
2MB L2
140 Million Transistors
90nm

Dothan also has improved Branch Prediction among other things.

More information on that can be found here.

http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2129&p=3
 
Looks like I've got a Dothan then. (BIOS reports 266MHz mem freq, so x2 = 532MHz).

Thanks guys. :D
 
Good choice to keep the Pentium M.

I would keep the Pentium M simply because Pentium-4Ms sucked so much ass. Hot, loud, power-ineffcient... horrible CPUs.
 
Looks like it's an 855GME based laptop, I think 400FSB CPUs are what it's limited to. I believe the fastest thing you could get is a Pentium M 765, 2.1Ghz CPU.

I can't confirm the chipset on that laptop though, so you may want to double check just in case. (I looked up some old ebay auction for the D600)
 
Yiffy said:
Looks like it's an 855GME based laptop, I think 400FSB CPUs are what it's limited to. I believe the fastest thing you could get is a Pentium M 765, 2.1Ghz CPU.

I can't confirm the chipset on that laptop though, so you may want to double check just in case. (I looked up some old ebay auction for the D600)
Click to expand...
Confirm with a lspci, or something eh?

I assumed it was 533 because BIOS reported memory running at 266MHz, so since its DDR, 266*2 =532MHz FSB.

@ the guy who suggested eBay, I just got stuck with 4 1GB sticks of probably fake/weird/off-brand SO-DIMMs from a seller in the forums who probably in turn got those off eBay as well. Though I guess if I find one from a reputable seller, might go for it.

IIRC, 2.4 is the fastest, I may settle for a 2.0 or 2.2. If the ratio of 1.6 P-M = 2.4 P4-M is constant/linear and not exponential or logarhtimic, roughly I'd be getting what, 3.0 P4-M (if existed) performance.

I think that CPU coupled with adding 2GB of Dell-approved RAM would make it last another few years at the minimum. :)
 
When your BIOS is reporting 266, it really means 133. It's already being doubled.

The P-M CPUs that ran at 100MHz FSB could run their memory at 100 or 133 so it's not a given that you have a chipset that can support a 133FSB P-M based solely on your 266 mem speed reported in the BIOS.

But if you do, I highly suggest looking into doing a pin/wire mod on your current CPU socket. You'd bring your 1.4 up to 1.867GHz. It would be a nice improvement for free.
 
BigBadBiologist said:
When your BIOS is reporting 266, it really means 133. It's already being doubled.

The P-M CPUs that ran at 100MHz FSB could run their memory at 100 or 133 so it's not a given that you have a chipset that can support a 133FSB P-M based solely on your 266 mem speed reported in the BIOS.

But if you do, I highly suggest looking into doing a pin/wire mod on your current CPU socket. You'd bring your 1.4 up to 1.867GHz. It would be a nice improvement for free.
Click to expand...
D'oh, right. Intel quad-pumps, so 100 = 400FSB, and 133 = 533FSB. Need to double-check w/ CPU-Z or something.need to get out of work and go home dammit.

What keywords should I google for to find a decent, detailed guide on the pinmod? "Dothan pinmod" or similar? And what are its side-effects? (Electromigration from increasing voltage, battery life decrease, etc).
 
Alright, did some research on it...so I could grab, say a 1.7 400FSB P-M off eBay for $25, pin mod to 533 and get 17*133=2261MHz? Sweet-ass. :D
 
well, the downside is that it just may not work and your battery life would be lower. But if you use a voltage and multiplier monitoring/changing program the battery effects should be negligible for basic system usage. I can't think of the name of the program I was using with my P-M (I'm on a MacBook Pro now, so I don't use that any more), but I'll try to find it for you.
 
Well, it won't matter now...I've got teh 855 chipset it seems, which has no headroom for 533FSB.

The only thing I'd be planning on doing now is snagging a faster 400FSB processor off eBay, and maybe undervolting it, if possible.
 
Your laptop should handle Dothan processors as mentioned, but again- only 400FSB models. Also, your chipset is 855PM, not 855PME; this means any memory you plug in will run DDR266, single channel. It'll roughly match your 2.2 now, but will come nowhere near a P4-3GHz because all that CPU power will leave it starved for bandwidth.
 
My 1.7ghz dothan beats my 3.06 prescott in super pi by 1 second (47s), owever when I overclock my pentium m to 2.2 ghz (using clockgen) I can do superpi in 35s Im thinking about trying to pinmod it but im not sure if pinmodding it to increase fsb will increase my ram speed (my ram is the limiting factor in my overclock)

Can someone tell me if pin modding my cpu will increase my ram speed?

Good choice on the pentium m btw.
 
Yeah, just found out that the D610 has the 915 chipset. Argh!

Oh well, can't beat rescuing a laptop from disposal for free, I guess. Putting some money into it won't hurt! Was playing around with it yesterday...3.5 hours of battery life whilst doing my usual post-Windows installation spree.

God, I love Pentium Ms. :D

Shameless plug, I have another identical D610 for sale if anyone wants it. A bit beat up, but all components are functional 'cept the optical drive, which doesn't seem to like DVDs anymore. 0
 
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