Thank you for being a valued part of the CNET community. As of December 1, 2020, the forums are in read-only format. In early 2021, CNET Forums will no longer be available. We are grateful for the participation and advice you have provided to one another over the years.

Thanks,

CNET Support

General discussion

Pentium-M discussion - needs a hardcore answer

Aug 1, 2004 1:53PM PDT

(It seems the Pentium-M is the only choice on a notebook nowadays on mobile computing)
Correct me if I'm wrong.

Is Dothan by all means completely better then Banias?
In fact, I don't think so.

Banias runs at slower internal and external clock speed, less cache, etc. You may wonder how is it not completely worse then a Dothan?

If you have heard about why Pentium4 failed the beloved Pentium series you'll know it. Here is the primary reason: Dothan have more pipeline stages to increase clock speed. Pentium-M Banias have 10 while Dothan have 12. Pentium4 have more then 20 for those who don't know.

Now let's see about the pipeline stages cycles per second.
Banias 1.5GHz vs Dothan 1.6GHz.

Banias 1.5G: 1500/10 (mil) = 150M
Dothan 1.6G: 1600/12 (mil) = 133.33M

In theory, Intel attempted to overcome the decreased pipeline stages cycle rate by improving the organization instructions of the pipeline stage system. They did a decent job here, as you can see dispite of the fact that Dothan 1.6GHz have double L2 cache, 50% faster external clock, it is somewhat on par with (or worse then) Banias 1.5GHz in terms of performance. Mostly because of faster external clock means faster memory, but that was not the bottleneck really.

And Dothan eats more battery since it has way more transistors as well. Add in the fact that Banias have a few ULV(Ultra Low Voltage) models at the moment, which is just the best mobile solution around.

Your comments?

Discussion is locked

- Collapse -
Re: Pentium-M discussion - needs a hardcore answer
Aug 1, 2004 9:07PM PDT

Gamers don't care about battery life (well they "wish"). And for gamers, the battery issue can be moot with dedicated video that is more power hungry too.

I agree you need to balance your objectives, but you can't force your view on all others. That's why there are choices to be made and why the P4-HT is available in a laptop. Yes the battery life is shorter, but it does work for those who can't do with less.

As an example, I have this C3 based mini-desktop that runs on well under 40 Watts of AC power. It's all of 733MHz but does fine for collecting weather data. But I wouldn't try a 3D game on it.

Bob

- Collapse -
Re: Pentium-M discussion - needs a hardcore answer
Aug 2, 2004 4:30AM PDT

For only $50 dollars more on a Compaq X1000 ordered custom online, you can move from the 705 1.5 Banias to the 725 Dothan 1.6. That is a no-brainer as they were charging $50 or more before to move up from 1 chip to the other when they were not different (both Banias).

The L2 cache mostly gives a bit more speed when you are loading frequently accessed web pages, etc. as it is much faster than using system RAM. When using a lot of programs it is more important to get a faster RPM hard drive (7200 or 5400 versus 4200 in notebooks standard).

The real performance boost is going to come when the new Sonoma chipset somes out at the end of this year or early next year that will support faster RAM and have new chips to enhance the Dothan CPU.

I have a Banias 1.4 Pentium M and it is fine for me but I would not hesitate to get a 1.6 Pentium M Dothan if ordering now due to the small price difference at that end of the spectrum. The 2.0 and 1.8 Pentium M's are way too high and most people ordering custom X1000 or ZT3000 machines (see X1000forums.com) are getting the 1.6 or 1.7 and adding a faster hard drive ($50 to $75 to get 5400 versus 4200 speed at same storage capicity of 60mb), 64mb dedicated video ($50 over 32mb when ordering custom), etc. to boost the overall performance. And, by only getting 256mb RAM from the manufacturer you can easily add a 512mb RAM stick for $100 or even less if on sale to end up with 768mb for less than the manufacturer cost for 512mb.

So, if you really want to see the vast improvement with the Dothan chip wait for new chipset but that will not occur likely until early next year.