[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: PISMO G4 UPGRADE - Does it make sense with linux?

Benjamin Herrenschmidt schrieb:

On Wed, 2005-06-29 at 16:09 -0500, vinai wrote:
On Wed, 29 Jun 2005, Rainer Gutkas wrote:

I'm thinking of upgrading my Powerbook Pismo (400Mhz) to a G4 (550Mhz)
and wanted to know if it maces sense under linux.
I run Gnome desktop and a CPU meter and it runs crazy when I open an
App, display flash movies, or try to look at dvd's
So probably the Altivec Engine could do a real good job?
But is it supported and will tis bring a good amount of speed, because
for a 150Mhz clockspeed increase this upgrade is too expensive for me!
Oh and by the way if anybody has experience with such an upgrade, i'm interested....
Bottom line - if the software does not use Altivec optimizations, it's
not worth it.  I got one of these upgrades, and I posted some benchmarks
of before and after results (under Mac OS X) of the performance of this
upgrade.  If you look at the site: www.xlr8yourmac.com, and check under
the CPU upgrades database, my entry for the Powerbook 2000 upgrade is on
the 2nd or 3rd page of listings.

I ran benchmarks using generic UNIX-ish software (LaTeX and gcc) and Mac
OS X software.  The performance in the non OS X software (i.e. non G4
optimized software) scaled with clock speed, while OS X software which
used Altivec showed a larger performance gain.  If you plan to twiddle
and tweak software, and learn a little about vector programming, it may
be worth it for you.  If you just want to install and go, this upgrade
probably won't be worth the price,  unless the software you plan to use
has already been optimized for Altivec.

Which is the case of dvd playback ... (libmpeg2 is one of the first
thing that was optimized for altivec in linux)


Thanks a lot Ben, this is a big point. Do you know if Gnome also would profit from altivec, because the Gnome display is what is really slowing things down

fn:Rainer Gutkas
adr;quoted-printable:;;Kleiststr. 36;St.P=C3=B6lten;;A-3100;Austria
title:Bakk. techn. (B.Sc.)

Reply to: