Mac: G5 Unveiled
by Fred Balin,
Created: July 6, 2003
Body ... da da da, da
Body ... da da da, da da da
With a combination of
reverential awe and in-your-face bravado, Steve Jobs
introduced Apple's new PowerMac G5 tower systems two
weeks ago at Apple's Worldwide Developers Conference at
Moscone Center and staked bragging rights to the world's
fastest personal computer.
Now we understand.
Despite it's unmatched
position as the technology company of simplicity and
elegance, of design and sophistication, of usability and
functionality, of hip and cool, Cupertino has a
Hey! Hey! Hey, hey,
For years no-nothing
technology analysts and PC bigots have kicked sand at the
Mac. "A toy." "It runs too slow." "Not suitable for the
Rubbish of course, and
yet it has had a corrosive impact. Externally, on
confused customers and internally, on the Apple core.
No matter each
extraordinary Apple design feat, the issue in certain
circles always returned to raw processing speed.
In recent years, Apple
countered with the G4's Velocity Engine, a special
high-speed processing unit on the chip, and again with
dual processor G4 PowerMacs. They also educated the
public that blindly using processor cycles as speed
equivalents was like comparing Apples to, well, oranges;
it was a Megahertz Myth. But not everybody listened or
And it hurt.
Despite the endorsements
of the creative and the learned, the soulful and the
expressive, the visionary and the thoughtful, we now know
deep down inside what the whiz kids at Cupertino really
Macho, macho Mac,
I've got to be, a macho Mac....
Macho, macho Mac,
I've got to be a macho ...
Da da da da, da da da da da. Da da da da, da da da da da
And now they may have it,
and, boy, are they feisty.
All that pent up
...so bad that despite
Apple's fanaticism about controlling new product
information, someone within the company accidentally
posted the G5 product news on the Apple Retail Store
website days before the unveiling. There it resided for a
few hours before, presumably, the Apple SWAT Team
restored order and carted the culprit off to pump iron at
an undisclosed landfill.
But Steve Jobs was in a
forgiving and joking mode at Moscone referring to the
miscue as an act of mere "premature specification."
The official G5
announcement from the CEO followed, "We are delivering
today, the world's fastest personal computer."
After that, the
specifications and speed tests conveyed the kind of
information only a deeply committed cross-platform geek
could love and meaningfully decipher.
2 GHz frontside bus
12 unit core
215 simultaneous in-flight instructions
Pairs of symmetric-integer, double-precision
floating-point and load/store units.
Wow, I think...
What's it all about,
Even he didn't know
completely, stalling after "it has massive branch
prediction logic." Then, a half-beat later: "I don't know
what it does... it predicts branches....it's a good
The audience laughed. But
seriously folks, how does the lay crowd know just how
good all these features are and what they amount
The Apple-hired testing
outfit, Veritest, documented that a prototype top-of-the
line G5s closely matches or surpasses the best Dell
systems in integer calculations and kicks butt in
floating point. Hot dog.
Apple's internal tests of
key hi-performance applications, show more dramatic
whippings with Photoshop, pro audio applications,
scientific analysis tools, and gaming. Sounds
But the new machines
don't ship until August so we won't hear from end users
like you for many weeks.
In the meantime, this
article is my attempt to more clearly and simply explain
what the new G5 seems to be all about via the best
sources I have on hand.
Thanks for coming along
for the ride, and let me know if you have input to
Making of the G5
In case you missed it,
Apple's flower power days together with its 6-colored
logo are long over. And despite its iconoclastic
rhetoric, Cupertino has now been hanging out at the gym
big time with IBM for 10 years.
The fruits of this
collaboration, which also included Motorola, has been the
Power PC Alliance and four major generations of chips
that drive Apple's PowerMacs. At the Developer's
Conference, we learned of Generation 5, the G5 processor,
Apple's trademark for IBM's PowerPC 970
The G5 chip is based on
one that IBM uses to run its highest performing
Describing the chip's
fabrication and physical specifications moved Steve Jobs
to tones of reverential awe.
Why? Because IBM's $3
billion dollar fabrication plant in Fishkill, New York
makes a G5 microprocessor:
with 58 million
transistors. ("I don't know how they count them.")
with transistors 130 nanometers wide, connected by
400 meters of copper wire less than 1/800th the diameter
of a human hair.
on a chip 118 square millimeters that is pressed
in groups onto 12-inch wafers.
all untouched by human hands in a robot controlled
"It's amaaazing," Steve
said, before pausing and repeating. "It's amaaazing." And
indeed it is.
The new G5 microprocessor
runs at speeds of up to 2 GigaHertz (GHz), which is
almost a one-third increase over the fastest G4 chip
running at 1.42 GHz. IBM expects to release chips running
at 3 GHz within a year.
In addition to the speed
boost, the processor is touted as the world's first 64
bit desktop processor. Both G4s and the fastest PCs use
32-bit processors. The major short-term benefit of the
64-bit innovation is application performance boosts
through minor revisions ("recompiling"). The new
processor also enables the use of up to 8 GB of memory
which only a small but significant group of users will
In the long term, 64 bit
processing may set the stage for a new level of
The 64-bit architecture
also supports 32-bit applications with no degradation in
performance. In other words, all your current PowerMac G4
programs running under Jaguar (Mac OS X v 10.2) are
supposed to work just fine in a G5.
In addition to the faster
and wider processor, information can be fed into the G5
chip at a much faster rate via a system bus that runs at
half the processor speed, e.g., 1 GHz on the 2 GHz
processor. This is 6 to 7 times faster than on the G4.
However Apple used other
tricks in G4 systems to compensate, including a large and
fast (Level 3) memory cache to store data close to the
processor, and a shorter and more efficient pipeline to
feed data instructions into the processor. This was the
crux of Apple's MegaHertz Myth campaign. With the G5,
Apple moves to more of a PC style processor with a longer
pipeline, no Level 3 cache, and a much faster bus. In
terms of microprocessors, the Apples and oranges are now
Also, on a dual processor
G5, there is a separate hi-speed bus for each processor.
The dual G4s shared the same bus.
In addition, the G5
microprocessor maintains the G4's Velocity Engine, a
speed feature PCs do not have.
So, in summary, the G5 is
a faster and wide processor. It works with a greatly
accelerated system bus rather than a Level 3 memory
cache. It employs a longer instruction pipeline composed
of less complex instructions, and it maintains the
special advantages of the Velocity Engine.
Directing the G5 is a new
system controller that Apple developed and is fabricated
in the same IBM plant as the G5 microprocessor. It is
designed to allow direct communication between subsystem
components avoiding bottlenecks.
Other components of the
G5 logic board, support new, updated, and familiar
technologies on the Mac.
The G5 employs a new hard
drive interface, Serial ATA, which utilizes hard drives
of the same name. Serial ATA provides faster data
transfer than Parallel ATA found on G4s. The G5 can house
a second Serial ATA drive. Each Serial ATA drive can hold
up to 250 GB for a grand total of up 500 GB of internal
storage. Each drive sends data over a separate bus,
alleviating a potential bottleneck with pairs of Parallel
ATA drives, which shared the same data path.
The Advanced Graphics
Processing (AGP) Slot which holds your video card has
been increased in speed from 4x to 8x and supports faster
and more sophisticated cards.
Expansion slots (for
SCSI, video and other cards) can take advantage of a
faster PCI-X architecture. Many, but not all, older PCI
cards will work in these slots. (The older, PCI expansion
technology is still found on the low-end of the three G5
Each of the three new G5s
has a 4x SuperDrive, same as on the latest
Audiophiles and sound
editors will be pleased to note the inclusion of in and
out Sony/Philips Digital Interfaces (S/PDIF) which allows
noise-free optical digital audio connections to decks,
receivers, and 5.1 surround sound systems.
The new Macs, also ship
with latest version of USB, 2.0. These ports are backward
compatible to the older, slower version 1.1. Version 2
exponentially increases bandwidth potential. Of course,
your device has to support USB 2 and be capable of
utilizing the faster bandwidth to make a
Until now, Apple has
avoided upgrading USB in preference toward FireWire for
hi-speed connections. While USB 2.0 rivals the original
Firewire 400 speeds found on all Macs of the past few
years, the new Firewire 800 doubles Firewire's effective
In any case, the new G5s
sport three of the newer, USB 2 ports and two USB 1.1
ports. They also contain two FireWire 400 ports and one
of the faster FireWire 800 ports, also found on Mac OS X
only booting PowerMacs G4s.
The PowerMac G5 can hold
up to a whopping 8 GB of RAM in the top two machines and
up to 4 GB of RAM in the entry model. RAM modules must be
installed in pairs.
There's a new case design
for the G5. It's made of aluminum. While most of the
ports are on the back, three are three conveniently
placed on the front, including headphones, USB 2 and
To add or replace
components, you remove the entire side of the G5
enclosure and a plastic air deflector within. Then you
have easy access to the innards.
To deal with heat from
the super-charged G5s, a new cooling system was designed
that includes the vented case design, air deflector, and
nine, yes nine fans. Yet, Apple's claim is that this
machine is twice as quiet as the latest G4. Given the
flack Apple experienced with one recent G4 model,
derisively termed "the leafblower," it is likely that
they has studied the noise issue carefully.
The G5 comes in three
basic flavors: 1.6 GHz single processor, 1.8 GHz single
processor, and Apple's proclaimed PC heavyweight
champion, 2 GHz dual processor. Current base pricing, is
$2,000, $2,400, and $3,000 respectively.
Steve Jobs highlighted
the aggressive pricing and followed up with comparable
rhetoric. After noting that the fastest Dell is priced at
over $4,000, he proclaimed: "From now on, if anyone tells
you that Apple's hi-end machines are more expensive that
PCs, you can tell them where to look."
So should you buy a new
If you like to be the
first in the neighborhood with new technologies, or if
you are primarily a PC junkie and have been thinking
about the Mac and OS X, go for it. Your time is
I am a more cautious
soul, and prefer choices and to hear from real-world end
users. Sometimes the former is not possible as when Apple
kills old models and has managed inventory well.
In this case, Apple has
hedged its bets, or maintained "alternate" price points,
depending on your point of view. Under the G5
announcement radar (and discussed in our last
newsletter), Apple introduced two new general classes of
PowerMac G4 (1.25 single and 1.25 dual GHz machines),
which are significantly less expensive than G5s or the
G4s of a few weeks ago and that boot into both OS 9 as
well as OS X. (The G5s are Mac OS X only machines.)
So unless you are working
in very hi-end digital video, audio production,
scientific analysis, game development, or image
rendering, or crave to be on the bleeding edge, I would
advise waiting. If you need a new tower Mac, get one of
the G4s. They are tried and true and will serve you well.
(Contact us for a needs analysis regarding your specific
But Apple's future
clearly rides with IBM and the G5 processor and
architecture. Does it represent the long-awaited dream of
Steve Jobs, for parity in performance and price with
hi-end PC desktops? If this system performs in the real
world as well as it preens on the Apple stage, it could
mark the beginning of a new era of Macintosh acceptance
within the mainstream PC world.
In any event, it's going
to be fun.