# Pentium M and ISO of Gentoo

## xavan

What ISO have I to download for my centrino Laptop?

pentium 3, 4 or x86?

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## matteo*

the iso for pentium 4..

it's written here: http://store.gentoo.org/index.php?item=17&action=viewitem

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## Wildhoney

i say the iso for pentium 3!

http://store.gentoo.org/index.php?item=16&action=viewitem

compiled my hole system for p3, runs like a charm.

have a T40p IBM Thinkpad.

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## hulk2nd

compiled my whole system for p4, runs like a charm.

i think there is no 'perfect' optimization for the pentium-m yet. someone posted a benchmark the average between penium3 and pentium4 optimization is the same. so doesn't matter what you chose atm.

greets,

hulk

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## Wildhoney

p3 optimisation ist better, trust me or you will die a horrible death.  Death comes often with a red hat, so watch out! 

scnr,

    Wildhoney

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## xavan

Well everybody has is own opinion.

When will the next version of gentoo comes?(with the 2.6kernel)?

Maybe with pentium M optimization

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## thundersteele

gentoo already has 2.6 kernel. This only depends on which one you choose when installing. You can change to 2.6 kernel any day. 

Optimization flags have mainly to do with gcc. Don't know if there are efforts to make an 

```
-march=PentiumM
```

flag available. It is not in the hands of gentoo developers (unless they are working on an own compiler, eg. gencc   :Laughing:  )

Gentoo could release a new version every day. It would be useless. emerge sync and emerge -U world holds everyone up to date. Perhaps a new version will is needed when (if) gentoo switches from devfs to udev. Don't know.

PS: I am using P4 and it works like a charm. Using anything else will cause your girlfriend run away, your car be stolen and your dog getting ill. It is your choise   :Twisted Evil:   :Very Happy: 

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## Wildhoney

 *Quote:*   

> PS: I am using P4 and it works like a charm. Using anything else will cause your girlfriend run away, your car be stolen and your dog getting ill. It is your choise

 

no girlfriend to mount, no dog to ride, car broken, so staying with P3!

:PPPP

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## xavan

Which kernel do you prefer for a laptop?

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## matteo*

 *xavan wrote:*   

> Which kernel do you prefer for a laptop?

 

personally with my asus athlonXP i use the latest 2.6 (test11), i have no problem with mouse and acpi (on the 2.4 i had some problems..)

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## thundersteele

me too. currently test10. Has all in, so you don't need special patchsets like AC-sources etc.

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## feffi

Hi dudes,

I only can recommend you a pentium III optimization. This has several reasons:

- Pentium-M is a redesign of a Pentium III (not a Pentium4)

- Gentoo systems (including my old) emerged with pentium 4 encounter situations from strange problems with portage or system-files to complete unrecoverable crashes

- Pentium-M has no HyperThreading, so all optimizations in this direction will be useless

If you don't trust me, search this forum and gcc forums and take your own picture.

BTW: If you need some hints on optimizing towards a Pentium-M look at my thread here: Acer 803 LCi Notebook Config (maybe a sticky?)

or THE thread on CFLAGS here

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## xavan

OK thx a lot

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## scrllock

 *_kev_ wrote:*   

> 
> 
> - Pentium-M is a redesign of a Pentium III (not a Pentium4)
> 
> - Gentoo systems (including my old) emerged with pentium 4 encounter situations from strange problems with portage or system-files to complete unrecoverable crashes
> ...

 

It is the pentium 4-m, not the pentium 3-m. With gcc-3.2.3 or newer, sse2 (which is supported by the centrino, and is implied by -march=pentium4) works great. Hyperthreading has nothing to do with compiler optimizations, but scheduling/smp stuff in the kernel. So as long as the iso is the latest, p4 would be the best/fastest to use. Good luck with Gentoo.

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## Mambo

should be able to use pentium3 and just specify sse2    :Confused: 

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## scrllock

but will that imply all of the other pentium-4 optimizations? no reason to not optimize for the processor you have, that's the point of gentoo.

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## thundersteele

 *scrllock wrote:*   

> 
> 
> It is the pentium 4-m, not the pentium 3-m. With gcc-3.2.3 or newer, sse2 (which is supported by the centrino, and is implied by -march=pentium4) works great. Hyperthreading has nothing to do with compiler optimizations, but scheduling/smp stuff in the kernel. So as long as the iso is the latest, p4 would be the best/fastest to use. Good luck with Gentoo.

 

Well, don't know what it is really. But it is a Pentium M, not a Pentium 4-M, that is another Chip. -march=pentium3/4 both works, -march=pentium4 had problems anyway some time ago, so for those who want to be safe perhaps p3 would be better, I don't think it makes much difference in performance.

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## gurke

the problems with arch pentium4 have nothing to do with the pentium-m, but with some bugs in gcc-3.2 and lower (sse code). they are definitly fixed in 3.3, but it seems to work with 3.2 ok, by now (the latest GRP is compiled with arch pentium4). i have mine running with the GRP for 2 month now (and upgraded a lot, too), and it runs without any problems. the pentium-m is not a "higher frequency" pentium3 (or "lower frequency" pentium4) like some people say, but a new chip-design, that supports all the command extensions of the pentium 4, so it should work fine with pentium4 settings.

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## LLoydBates

USE="mmx mmx2 sse sse2 [..]"

CFLAGS"-march=pentium3 -mcpu=pentium4 [..]"

i'm running my Centrino with this .. compiled from stage 1 

works wonderfull

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## TenPin

http://www.ussg.iu.edu/hypermail/linux/kernel/0310.0/0398.html

 *Quote:*   

> 
> 
> While it has some P4-like extensions, the P-M core is P6 not NetBurst.
> 
> This is trivially deducible from various Intel documents, including
> ...

 

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## Adamal

The pentium M is neither a P3 or a P4.  It is the first processor that was designed from the start with mobility in mind.  You could say that it is a cross between the best features of the pentium 3 and 4.  I don't think you could go wrong with either optimizations, but I believe that the P4 optimization would be better for this processor.

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## jcmorris

If you do a cat /proc/cpuinfo, you'll notice that it is in the P6 family.  It is based on a modified P3 core, with some Pentium 4 extensions, such as SSE2 and a faster bus.  Doing a heavy googling, and after reading a bit of the Intel Optimization guide, and reading discussions between developers, it seems to me that it is best to optimize for either a pentium 3 or i686 (I don't think you'll notice much of a difference).  Here are my CFLAGS:

-march=pentium3 -msse2

I think those would be the best processor optimizations.  Oh, and definitely optimize with -O3 and possibly -funroll-loops.  The P-M has a 1 MB L2 cache, use it!

jcm

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## jcmorris

Oh, and one more thing guys, make sure you compile the kernel for a Pentium 4, because I'm not sure, but I think it needs this in order for the kernel to support SSE2.

jcm

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## jcmorris

 *LLoydBates wrote:*   

> USE="mmx mmx2 sse sse2 [..]"
> 
> CFLAGS"-march=pentium3 -mcpu=pentium4 [..]"
> 
> i'm running my Centrino with this .. compiled from stage 1 
> ...

 

Hmmm, I think you have -mcpu and -march backwards.  -march=pentium3 enables the P-3 ABI (SSE, MMX, etc), but you are making GCC time things for a P-4.  This should be reversed, -march=pentium4 -mcpu=pentium3.  This will enable SSE2 and time things for a Pentium3-like processor.

jcm

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