Friday, December 21, 2001
Below we provide a performance review of the
PowerBook G4/550 compared to the iBook G3/600 when running
OS 10.1. In most of our OS 10.1 tests, the G4 PowerBook bested
the higher clocked iBook ... sometimes by a large margin.
This was not always the case with the testing we did comparing
these machines when running OS 9.2.1.The G4 processor of the
PowerBook is the chip that Apple markets as having a 'Velocity
Engine'. The more technical name for this enhanced processing
capability, is 'AltiVec
Technology' which is carried out by a 128-bit vector engine.
"The AltiVec unit is an enhanced integer or floating
processing unit. It provides a new 128-bit processing unit,
32 vector registers and over 160 new instructions that allow
for the processing of data in a pipeline"
Aside from the G4's ability to improve performance significantly
in certain programs tuned to take advantage of it, (see the
AltiVec Fractal test below, to see just what can be done),
OS X itself, must have been tuned by Apple to, in some of
its parts, take advantage of the Velocity Engine. This would
account for some of the relative speed improvement of the
PowerBook when running OS 10.1 over the PowerBook when running
similar tests under 9.2.1.
Of course raw performance capability is not the only criteria
to weigh when selecting a portable computer. But if your rely
on your machine to do heavy lifting the results below should
give you some guidance on what kind of work each excels at.
Be sure to check out the links under "Additional Resources"
for more information on these machines.
"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
iBook G3/600, 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
This result was similar under both OS's.
Perhaps the better graphics sub-system is what is helping
the PowerBook here. But is could be that AppleScript is tuned
to take advantage of the G4. 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. Both these machines have a 256K L2 Cache. Though
the PowerBook is faster, both are hobbled by the small cache
Number Crunching & Rendering Tests
In the processor intensive tasks above you can see the power
of the G4 coming into full force. 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
Where possible, most Apple programs have been
tuned for the G4 processor .. see iTunes
Well you can't win at everything .. see StuffIt