Friday, December 28, 2001
Below we provide a performance review
of the PowerBook G4/550 compared to the PowerBook G4/500,
when running OS 10.1.
The 550 MHz machine has a 100 MHz System
Bus, a slightly higher processor clock speed, 256K of
full processor speed,on-chip L2 cache and a faster graphics
system, with 16 MB of dedicated graphics memory.
The 500 MHz machine also has a 100 MHz
System Bus, in place of the on-chip cache it has a back-side
cache of 1 MB running at half the processor speed. It
also has a slower graphics system and only 8 MB of graphics
As you will see from the scores below,
the lack of a large back-side cache in the newer 550
MHz PowerBook, stunts its performance in some tests,
when compared to the older 500 MHz PowerBook. However
the smaller speedier on-chip cache seems to have made
a big difference in one of our drive related tests,
where faster calculations on smaller amounts of data
were called for ... at least when running under Mac
If you are a person that likes to play
demanding games on your portable, the new 550 MHz PowerBooks
really shines over its predecessor, turning in 130%
better performance when running Quake III in 'Quality
So the overall performance of the new
low-end PowerBook is somewhat mixed, both when running
under Mac OS X and when
under OS 9. It is however Apple's budget professional
portable. The previous 500 MHz machine was Apple's top
of the line portable in its time. The 500 MHz machine
cost $3,499 when it was first released. The PowerBook
550 MHz machine was $2,199. So you get slightly worse
performance in some areas, much better performance in
some areas, all for $1,300 less.
"Real World" Tests
The tests below are from our suite of real world application
tests. These tests feature a diverse selection of applications
commonly used by the Mac community. The test suite was designed
to render an accurate and well rounded picture of a machine's
performance. All of the tests below were timed with a stopwatch.
The times are then converted to percentages relative to the
PowerBook G4/500, which is set to 100%. For all scores, higher
numbers are better.
Drive performance is what probably makes
the most difference in the above test
This was an interesting result because the perforrmance was
almost the opposite when
running under 9.2.1. Our feeling is that the fast 256K
of on-chip cache is what is helping the score of the newer
PowerBook. In some way OS X appears to be able to utilize
this speedy memory better than OS 9
This result was similar under both OS's.
Why the smaller cache of the 550 MHz machine would be an
issue hampering performance in this test is unclear.This test
creates and destroys 1,000 windows. See the program
site for more info
Large document is scrolled from one end to
the other using Classic OS through OS 10.1
Large Document & Database Type Test
This test takes place in a large AppleWorks
document. This results is also somewhat of a mystery. In past
comparisons we have noted that a larger, but slower, L2 cache
does better in this test than a faster smaller cache. Indeed
when comparing these two machines under OS 9, this is the
case ... by a wide margin. So why the newer PowerBook is doing
better here, under OS X, is not clear.
Number Crunching & Rendering Tests
Obviously the newer PowerBook has a lot of processing punch,
when it can be tapped. The Fractal
program has been highly tuned to take advantage of the G4
and is precisely the type of work that the G4 was made for.
This test gets movie files ready for Web streaming
movies to DV allows you to import them into iMovie
The above 3 test require a lot of data fetching
and it appears that the larger cache trumps a faster processor...
Pretty much a tie .. see StuffIt
A Sorenson encode and the AltiVec Fractal
are performed at the same time... no clear lead means the
slower clocked PowerBook is the winner.
Here the Sherlock Index Test and the AppleWorks Search and
Replace tests are run at the same time. Curiously the 550
MHz machine beat the 500 MHz one when these two tests were