August 20, 2001
Last week we looked at the performance
of the new Quicksilver G4/733 and compared it to numerous
other Macs, but in particular to the last generation Power
Mac single processor G4/533. In that showdown we found that
in many of the tests the 533 was just as fast as the 733.
And in the other tests the 533 bested the 733, sometimes by
a significant margin. We explained this away by claiming that
the lack of a backside cache in the 733 hampered its performance.
In most tests this cost the 733 a modest hit on the performance
meter, but on other tests the hit was significant.
Since then we have got our hands on a Quicksilver
867. Where the 733 has only a on chip cache running at full
processor speed, the 867 not only has a faster clock-speed
but also has the same 256K on chip cache (again at full processor
speed) plus 2 full MB of backside cache running at one fourth
the processor speed. On a purely MHz basis the 867 is only
18% faster. Yet in many of the tests it turned in anywhere
between a 24% - 145% speed improvement over its younger sibling.
However, there were some tests in which the 867 flunked out
- namely in tests involving the optical drive.
Anyway take a look at the results below. We
have included our best guess about what is going-on to generate
these differences. If you have a better explanation, or a
different opinion, please let us know. Either e-mail
us a message for us to post or use this link
to post your ideas on our bulletin board
Both machines were configured similarly and
running OS 9.2
Note: This is our initial look at the performance
of the new Quicksilver towers. We will be running more tests
and hope to have a full review of all the new Power Macs in
the next few weeks.
"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 (with the exception of the Quake III & CineBench
2000 tests) were timed with a stopwatch. The times are then
converted to percentages relative to the slower machine which
is set to 100%. For all scores, higher numbers are better.
In rotational speed the 733 is slower than the 867. So why
is the 733 faster in this test. Different drives handle data
differently. One drive may be faster at reading data, one
drive may be faster at writing data. One may have an easier
time with large single files and another may be faster reading
and writing small bites of data. The test above copies a folder
containing thousands of files.
Reading and writing a single, large data the 867 is a clear
winner here. Perhaps also the existence of the backside cache
is a factor.
AppleWorks 6 Tests
The additional speed of the 867's processor and and the backside
cache account for the increased performance here - the drive
is not a factor.
OK, here is where the machine with the backside cache comes
into its own. The document we use is 1.5 MB ... theoretically
it could all fit completely into the 2 MB backside cache of
the 867. On the 733 without any kind of backside cache the
processor must trudge all the way to main memory to get much
of the information it need. So if a lot of your work involves
large databases, spreadsheets or document you will want to
be sure to consider one of the machines with a backside cache.
On small documents (under 256K). The performance difference
will not be that great.
Quake III Tests
These scores are relative.
Here again the processor speed and improved
memory subsystem gives the 867 its disproportional advantage
Why nearly identical results here? Both machines have the
same graphics card and at high-quality setting it appears
the Quake is running exclusively off the card ... using the
other subsystems little if at all.
Photoshop 6 & Other Data Crunching Tests
We use an 20 MB image to launch Photoshop. Here the drive
plays a part as does the processor and memory subsystem. A
lot of rendering is going on here not just hard drive activity.
These two Photoshop test (above and below) are carried out
completely in RAM - there is no drive activity. Again the
867 has a disproportional speed boost.
The effect is even more in evidence here.
The 733 did quite well in this test, though
still 10% less than it should when clock-speed is accounted
This test stresses both the processor and
its subsystems and the graphics card
Again we see a similar pattern. The hard drive is accessed
here but is not much of a performance factor as it can deliver
data much faster than it can be processed.
Good for you 733! The 733 has a 32X CD drive and the 867
has a 24X CD drive. The file being converted is coming off
Hard drive is a partial factor here.
The 733 writes CD-Rs at 12X and the 867 at