Not long ago, an enthusiastic SPCR reader submitted a User Review of an Apple iMac. Readers enjoyed his review, but clamoured for official SPCR noise testing. Well, we’ve delivered. Our official SPCR review of a 17″ Core Duo-based iMac confirms what Randy Harris knew all along: The iMac is quiet, energy efficient, and excellent value to boot. Oh, and it can also run Windows…
April 21, 2006 by Devon
Cooke with Mike Chin
|Apple 17" iMac|
|~US$1500 from the Apple Store|
By now, most people are aware that Apple makes quiet systems, especially those
based on Intel’s Core Duo processors. We recently published a
user review that said as much. However, until now we haven’t been able
to say exactly how quiet. An oft-repeated criticism of the user review
is that the noise impressions were subjective and unquantified — not really
a surprise for a user review, but a legitimate complaint for readers who wanted
to know more about the product.
So, we pulled a few strings and managed to convince Apple Canada to send us
a unit that we could measure and abuse in the comfort of our lab. On a rainy
morning a couple of weeks later, a surprisingly small box showed up holding
the most tightly integrated "desktop" system we’ve ever seen. In fact,
with the exception of the full-size keyboard and mouse and the lack of a battery,
the iMac might as well be a laptop, albeit a very full-featured one.
This modest-sized boxed holds a complete system, LCD monitor included.
Five minutes later, we had plugged the AC cord into the wall, hooked up the
keyboard and mouse, and were happily surfing the internet courtesy of the internal
wireless card. No drivers to install, no pop-ups asking if we’d like to purchase
broadband access from a major Telecom, and no "friendly" reminder
that we’d be locked out of the operating system if we didn’t activate OS X.
Our impression was that the Core Duo iMac is very fast and snappy — much more
so than the previous PowerPC Macs that we’ve used. We were pleased to notice
that the operating system took very little time to boot (less than half of what
we’re used to), and the system didn’t struggle at all with the heavyweight GUI
that ships with OS X. Although detailed performance testing of the processor
is beyond the scope of this review, The
Tech Report recently did some extensive tests on the Core Duo and declared
it the best Intel processor yet.
For such a small package, the iMac is very fully featured. Wireless Internet,
a webcam, and a HTPC remote control (and software) are all standard features.
Things are the same on the software side of things. There is native support
for .PDF files (and it’s faster than Adobe’s version for Windows),
as well as GZipped archives and several common disc image formats. Apple’s iLife
suite of multimedia applications is more complete than Windows’ offerings and,
more importantly, is easier to figure out for first time users. It also comes
with the ability to play (and burn) DVDs — something that requires bundled
software on a Windows-based machine.
The complete system configuration is listed below, along with a cost comparison
using the same or similar parts, priced as cheaply as we could find them using
Apple 17" iMac Cost Comparison
Equivalent PC Part
Lowest market price
Proprietary to Apple
Asus N4L-VM DH
Seasonic S12 330W
BenQ FP71G+ 17" LCD
1.83 GHz Intel Core Duo T2400
DDR2 PC5400 — 1.5 GB
ATI Radeon X1600 128MB DDR3 VRAM
Sapphire ATI Radeon X1600 Pro 128MB
Maxtor 6L160M0 — 160 GB
SuperDrive 8x (Identifed as a Matsushita DVD-R UJ-846)
Wireless Network Card
AirPort Express (w/ Bluetooth)
MSI Dual Net Card
Logitech Labtec WebCam Pro
Keyboard + Mouse
Keyboard & Mighty Mouse
Logitech Deluxe Desktop Keyboard & Optical Mouse
OS X Tiger (10.4.2)
Microsoft Windows XP Home OEM
Microsoft Works Suite 2006
As configured, the iMac is only about 10% more expensive than the parts priced
individually. Consider what you get for the extra $150:
Apple’s reputation for being expensive may be justified for some of their products,
but the 17" iMac is not one of them. Time will tell, of course. Once big
names like Dell and Gateway begin selling Core Duo-based systems, the cost of
the individual components may drop, but for the time being the iMac is one of
the cheapest way to obtain a system built on a Core Duo.
Although it is not the focus of this review, Apple’s home theater software
deserves special mention for being easy to pick up and figure out immediately.
Anyone who has used an iPod should be able to figure out the interface in minutes.
Surprisingly, the tiny Apple Remote, with just five buttons, is perfectly adequate
for navigation. Its secret is tight integration with iTunes. Media is organized
in iTunes (or iPhoto for pictures), where it can be sorted into playlists and
identified by Title, Artist, etc.
Then, the home theater mode is activated by pressing any button on the remote.
Icons and text are large enough to be seen at a distance, and selecting media
to be played is as simple as navigating the menu system for the iPod.
Its biggest advantage over Windows MCE, iMon, etc. is its simplicity. It does
not expect you to do everything by remote, and the options and everything else
has been cut down to the bare essentials — making it simple to do what
you want to do with a remote: Play media.
The iMac glows with sleek glossy sex appeal, like a powerful, oversized iPod.
In comparison to a conventional desktop, the iMac is impressive for its small
footprint and the lack of cable clutter. Only three cables need to be plugged
in: The AC power cable, and the keyboard and mouse. Those who are willing to
pay a little more can eliminate the cables for the keyboard and mouse by springing
for Bluetooth-enabled wireless versions.
The small footprint is even more visible from the side: It’s only slightly
thicker than a standard LCD screen.
Apple has done a good job of disguising the fact that there’s a whole computer
bundled behind the LCD monitor. The front bezel is completely smooth, with no
buttons or ports to mar the finish. The only functional parts are the screen
itself and a tiny black spot that hides a webcam and an infrared receiver. One
other functional feature shows up when the system is put to sleep: A hidden
LED glows white under the surface of the bezel to indicate that the system is
not powered off entirely.
So where are the functional parts hidden? Most of the ports for the peripherals
are located on the back of the unit, where they are invisible under ordinary
circumstances. Some users may object to the lack of front ports, but it really
isn’t too much trouble to reach underneath the screen to plug something in.
If you can’t do it by feel, the small form factor makes it easy to spin the
screen around. This isn’t a desktop box sitting underneath a desk. There are
also two USB ports hidden on the top edge of the keyboard, but they are unpowered
and would not recognize our USB flash drive (Apple’s "Mighty Mouse"
Apple is quite aggressive about dropping legacy ports, so the number and type
of ports is quite reasonable. From left to right, the connectors are as follows:
A neat line of external connectors.
In comparison to most Windows-based systems, there is less
variety and fewer connectors overall, but for most users there should be enough.
After all, when was the last time you used all eight USB ports that your motherboard
Power users may be annoyed by the … unusual … choice of connectors for
the DVI and SPDIF ports. Here Apple is engaging in a bit of market engineering.
Not surprisingly, the only other hardware that supports these kinds of connectors
are Apple and a few traditional manufacturers of "Apple only" peripherals.
Adapters are available, of course, but at a significant premium.
A slot-loading DVD drive is hidden in the right side.
One final bit of sleekness is the position of the DVD-burner. Only a thin slot
along the right side of the screen shows that the iMac comes with any kind of
optical drive at all. The slot feeds into a laptop-sized drive manufactured
by Matsushita (better known outside Japan as Panasonic). Once again, power users
may be annoyed that the drive cannot be replaced with a standard part, but by
now it should be quite clear that this product is not targeted at that market.
If nothing else, the unusual loading mechanism serves to enhance the image
of sleekness and exclusivity — something that Apple is no doubt quite aware
of. From an ergonomic point of view, we are quite in favor of the slot loading
drive. Questions of reliability aside, a slot loading drive is both simpler
to use and often quieter than a tray-based design.
AIRFLOW & COOLING
Given how important thermal
design is to achieving low noise levels, it’s quite impressive that there is
almost no visual evidence of thermal design: No fan grills, no wide-open (or
even restricted) intakes, and no visible heatsinks. The evidence is there if
you look for it, but even then the surface area of the intakes and exhaust vents
is shockingly small. No doubt the low-power Core Duo around which the iMac is
based helps keep heat down a bit, but even then it’s surprising how little airflow
there seems to be.
Most of the bottom serves as an intake, but the intake grill is quite restrictive…
The main intake is located on the bottom, where more of the thick plastic casing
has been cut away to reveal a thin (but restrictive) metal grill. The amount
of air flowing through the system must be very small, since no airflow could
be felt at the bottom even with the system running full tilt.
There is another small opening in the center of the back panel … but is
it an intake or a speaker?
There is another small vent on the back panel, but no airflow could be felt
The slim white strip at the top is the only point of exhaust.
The exhaust vent is a thin indented strip that runs across the top of the back
panel. To a casual observer, it appears to be part of the system’s cosmetic
design. Only the slight trickle of hot air that we could feel drifting from
it betrayed its true function. Even so, the amount of air passing through the
system is probably not much more than would be achieved with convection alone.
In addition to the small amount of airflow, some cooling is also provided by
direct conduction. As a heatsink material, the plastic exterior has nothing
on copper or aluminum, but there is enough surface area that it probably helps
a little. In this respect it is like a laptop, which also dissipate heat through
plastic. The back of the screen got quite warm to the touch, confirming that
some heat was being transferred in this way.
Testing on the iMac was quite simple in some ways, and very complex in others.
Because it is a complete system, there were no drives to suspend or fans to
tweak, so measuring noise was as simple as placing the sound meter one meter
away and taking a reading.
Power and thermal testing, on the other hand, was complicated immensely because
we are unfamiliar with any of the hardware monitoring and benchmarking tools
available for OS X. And, for some reason none of the OS X-based utilities that
we downloaded could detect any temperatures other than the SMART data from the
hard drive. Because of these limitations, our stress testing consisted of running
a custom-compiled version of CPUBurn
for a long period of time and hoping that nothing crashed.
The ambient noise level at the time of testing was 17 dBA@1m.
iMac: OS X
AC Power Draw
Low Power Idle
HDD Seek @ Idle
2 x CPUBurn
With a maximum power draw of 63W, the iMac certainly qualifies as a low power
system. At idle, the system drew 46W, which will qualify for approval from EnergyStar
if their current draft computer spec makes it to the planned 2007 release. Even better, the system falls
back into a low power mode after being left alone for a few minutes, dropping
the power even more to just 33W. By way of comparison, the lowest idle power consumption
we’ve ever seen from a custom built system is 36W — and that doesn’t include
an LCD monitor.
Much of the power savings in the low power mode seems to come from a reduction
in the brightness of the LCD screen, which drops to the lowest possible brightness.
This sometimes got quite irritating, since the low power mode sometimes kicked
in while reading a large block of text on a web page and the mouse would have to be moved around to boost the brightness back up. One solution might
have been to turn the brightness down all the time,
but this might not be practical in a brightly lit room.
If the system was left alone for much longer — about 15 minutes —
the system would shut itself down into standby mode, where the total power consumption
dropped to just two watts. Like the low power mode, this also had its drawbacks.
In fact, it had a habit of shutting itself down while we were running CPUBurn,
making it difficult to sustain the test for a long period of time.
The energy efficiency of the iMac solves the mystery of how it is able to get
away with so little cooling. At first glance, the numbers don’t look that impressive,
but keep in mind that all of these numbers include the power required by the
LCD screen. Stand-alone LCD monitors typically draw between 30~40W from the
wall, so we were quite impressed when the entire system managed
to draw this little power.
The noise levels were no less impressive than the power efficiency. At idle
(that is, most of the time), the noise level was a paltry 20 dBA@1m, but even
then the noise was barely distinguishable from the ambient noise in the lab.
The noise character was very smooth, mostly a slight whirr masked by airflow
that sounded like the hard drive. Although the iMac contains a full size 7,200
RPM drive, there was surprisingly little low frequency hum. The secret may be
the metal stand, which seemed to absorb much of the vibration from the drive.
The drive vibration could be clearly felt by placing a hand on the back panel,
but a no vibration at all could be felt at the base of the stand.
Seek noise from the drive was plainly audible, and was the most annoying feature
of the iMac’s sonic character. It was much more audible than the measured difference
suggests, primarily because the clicks did not fade easily into background.
We did not get a chance to test whether AAM was enabled. If it was not, the
issue of seek noise might become a non-issue.
Although the noise levels did rise slightly with CPUBurn running, the increase
was almost imperceptible. In fact, if we hadn’t measured the difference, we
probably wouldn’t have noticed — the noise character did not seem to change
at all. Only the sudden realization that the iMac was easier to hear against
the background noise convinced us that there was any audible difference at all.
iMac: Optical Drive Noise
As is the case for almost any system, the optical drive was a significant source
of noise when it was in use. At full speed, it measured 31 dBA@1m — not
quiet, but better than most full-sized drives. Subjectively, it also sounded
a little bit nicer: It was smoother and sounded less mechanical. The bulk of
the noise was a clean whirr floating on a bed of airflow noise, with very little
low frequency hum. The better subjective quality can probably be attributed
to the well-sealed slot, which didn’t let much noise out, and to the thick plastic
body of the iMac, which is much less prone to resonance than aluminum or steel.
Fortunately, the full blast noise level of the optical drive only lasted for
about thirty seconds, even when the drive was in heavy use. After that, the
noise level dropped to a respectable 24 dBA@1m, where it stayed while the drive
was in use. Once the drive had stopped being accessed, the noise level dropped
even further to 21 dBA@1m, where it was completely inaudible unless specifically
listened for. When left idle for another ten minutes, the drive stopped spinning
GOING TO BOOT CAMP
Not a day after we completed our testing, Apple announced that their Intel-based
systems would be supporting Windows XP via a firmware update known as Boot Camp.
An update to OS X would also allow the default operating system to be selected
and changed. This provided us with an excellent opportunity to run a test with
our standard tools. We jumped at the chance in hopes of being able to access
the thermal sensors.
The Mac side of the upgrade was quite painless. Step by step instructions guided
us through the procedure of updating the firmware to emulate an 8088 BIOS, burning
a Windows-compatible driver disc, updating OS X, creating a Windows partition,
and then finally rebooting the system to begin the Windows installation process.
As usual, installing Windows was an overly long process, but it proceeded without
any more troubles than usual. Care had to be taken to select the correct partition,
but no other special procedures needed to be followed.
Once Windows was installed, the Apple-provided driver disc provided drivers
for all of the essential hardware, but even with the drivers fully installed
there were still a few unrecognized devices in the Device Manager.
Apple explicitly states that iSight (the webcam) and the Apple Remote (for
HTPC functionality) are not supported under Windows XP, but a webcam did show
up in the Control Panel under Scanners and Cameras. Double clicking on this
icon immediately produced a Blue Screen of Death. Next time we’ll listen to Apple,
but it was entertaining to see an iMac with the Blue Screen of Death.
Something we never thought we’d see: The Apple and Windows logos side by
Alas, our hopes of being able to see the CPU temperature were in vain, as SpeedFan
4.28 did not detect any thermal sensors aside from SMART. Once again
we were stymied. However, we did manage to run CPUBurn again and ATI
Tool to stress the graphics subsystem. We also tried to run Throttlewatch,
but once again we were unable to detect anything of use — it reported both
versions of Intel’s Thermal Management as being disabled.
iMac: Windows XP
AC Power Draw
Idle (LCD Brightness @ Minimum)
Idle (LCD on standby)
2 x CPUBurn
2 x CPUBurn + ATI Tool
Surprisingly, power consumption was higher across the board when Windows was
running. Only at idle was the difference small enough to ignore. With CPUBurn
running, the power draw was three watts higher — quite shocking because
the code should have been identical down to the instruction. CPUBurn is coded
in x86 assembly, so there should have been no differences in the final code
that was executed. Presumably, differences in the way OS X and Windows schedule
the tasks are responsible for the differences.
We were able to push the power consumption even further when we ran ATI Tool
alongside CPUBurn. The end result was a system, LCD included, that drew a total
of 73W from the wall — an amazing result for a full CPU and GPU stress
test. Even during this intensive test, the noise level never rose above what
it was with only the CPU under stress.
Because Windows did not support the low power idle mode that was present in OS X,
the idle power level never dropped quite as low as it did in OS X. Manually
turning the LCD brightness down to minimum (via an Apple supplied tool in the
system tray) dropped the power by ten watts, but even that was not enough to
match the 33W level reached by OS X in low power mode. Clearly, OS X disables
other features as well as dimming the LCD. In fact, even when the LCD was turned
off entirely by tinkering with the Power Management settings, the power level
was still above what OS X achieved with the LCD dimmed. Assuming that Apple’s
drivers allowed Windows full control over the motherboard, this seems to indicate
that OS X is more effective at reducing system power — notebook users take
The 17" iMac has almost everything a silencer could want. It’s quiet,
efficient, good value (never thought we’d say that about an Apple), and it can even run Windows. It is also the only Core Duo-based "desktop" system currently available. We want one.
More than anything else, it was the ergonomics and design that impressed us
about the iMac. Ordinarily, we rarely go for form over functionality,
but, so long as you’re willing to leave it alone without tinkering, the iMac
is perfectly functional. It is difficult to quantify exactly how the iMac succeeds
so well, as the difference is qualitative. The iMac has the feel of a luxury
sedan, a Mercedes perhaps. Sure, a Lamborghini or a souped up Civic is more
thrilling, but for sheer comfort and ease of use it’s hard to beat the iMac.
The one exception is Apple’s "Mighty Mouse". Although it pretends
to have a scroll wheel and "two button" functionality, using the tiny, hypersensitive ball to scroll up and down was frustrating, and
it took one of us the better part of an hour to master right clicking. The arrow movement is also too slow, even at maximum speed.
It’s ironic that Apple would be the first company to take an Intel processor designed originally for mobile use and create such a compelling product. The question is whether any of the Windows/PC companies will come up with a viable competitor to the Core Duo iMac. Surely, there is a market for such a product!
Long story short, the iMac is a computer for the connoisseur and for "Everyman", just as Apple
intended. Power users, enthusiasts, anyone who wants to tweak the hell out of
everything should probably stick to building their own systems — they’ll
be happier molding the computer to their own personal quirks. However, for those
who want to use a computer, not take up computer building as a hobby,
the iMac is among the best there is.
Much thanks to Apple
Canada for supplying the 17" iMac sample for us to review.
SPCR Articles of Related Interest
Eternal link: Kodawarisan’s Photo Tour of Core Duo iMac
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