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MacWorld's iMac Core Duo Benchmarks Debunked?
madgunde writes "Looks like MacWorld magazine was a little premature in reporting that the new Apple iMac Core Duo doesn't live up to Apple's speed claims. The folks over at MacSpeedZone have done some performance testing of their own that debunks MacWorld's results and shows that the new iMac Core Duo DOES live up to the hype. Not only did the new iMac wipe the floor with the old model in their tests, but using MacWorld's own test methodology would allow MacSpeedZone to conclude that the new Intel iMac is almost as fast as a PowerMac Quad G5. " I see only one way to solve this: Give me one. I'll run WoW on it, and decide.
How many stories can we have about the Intel-based iMac's benchmarks?
1 2/2478
All of these "benchmarks" are true, as far as they go.
Apple's original SPEC benchmarks are "true".
Macworld's "real world" application benchmarks are "true".
And now, MacSpeedZone's further tests of various tasks also are "true".
I mean, obviously the new iMac isn't going to be 2 times faster for everything under the sun. In fact, Jobs even spoke to this fact in the keynote when he directly said that the tests were just for the CPU and that everything else, like disk I/O and other subsystems, weren't all twice as fast, but it was to illustrate the performance (and performance per watt) of the new Core Duo, which is indeed impressive by any measure.
I think it's safe to say that the new iMac running native applications is definitely faster - sometimes up to twice as fast, and sometimes even more - than the iMac it's replacing. And Rosetta is so impressive that while non-native applications will run slower, it's damned good until native versions of those applications come out, too.
And speaking of CmdrTaco's request for a WoW test on the new iMac...
http://arstechnica.com/journals/apple.ars/2006/1/
"It's fast, fast as in a superlative and not a comparative sense. One wonders why Steve Jobs didn't blow the crowd away with the saturated colors and excessive frame rates of WoW on an iMac. It loaded fast, and when the first character popped up in town, the frame rate never dropped below 60, and this was pretty much going full tilt in the settings."
MacWorld uncovers secret Apple contributions to MacSpeedZone.
OR
Prices for flying pigs drop dramatically as supply increases after Apple products live up to claimed bench marks.
i'm completley convinced that for using email, web browser, iPhoto, etc.. that the new iiMacs wipe the floor with comparably priced PPC macs.
what i want to know - and what holds me back from moving to an iiMac from my DP g5 1.8 - is
1. how they will perform when rendering with Compressor
2. how much faster is FCP when hooked up to similar disk packs (like cheap desktop FW400 raids)
3. Will i still be able to run background processing tasks like Compressor and handbrake yet get good foreground performance so i can email, websurf and get on with life while waiting for those 30-1 hour long tasks, instead of walking away from the machine, lest i get tempted to use it and really slow down the renders.
4. Will Aperture stop sucking performance wise?
guns kill people like spoons make Rosie O'Donnell fat.
It's time for Blizzard to step up to the plate and use the massive amounts of money we give them monthly to get some better servers. I'm not so good with math but 5,000,000 users paying 12 dollars a month is .... $60 million?
most of it goes to NPC salaries. [/deadpan]
AltiVec! Velocity Engine!
I thought this was the best CPU technology?
Steve Jobs told me I had a super computer when I bought
my G3, G4 and G5.
My PowerPC processors were unique. It made me special. Anyone
can have an Intel processor. Even poor people. How is that exclusive?
I'm an upper middle class elitist snob. Why did Apple take away my bragging rights! Now I'm a technological nobody. I'm plain and boring again. For pete's sake, poor people can even buy IPODS now!!
I want my super computer back! Because I lack a personality and I have no soul what product can help? Please Steve Jobs tell me what to buy to get my soul back. What can I buy so that I feel whole again?
What about a Hybrid car, will that help me?
Microsoft says their software is secure...
Oracle says their database is hack-proof...
Symantec says their software protects me from hackers...
That's the point of the article. The Macworld article never considered processor useage. They said the new Intel Mac is "10-20% faster" without considering whether their benchmarks used the full capacity of the processor. They claimed that Jobs' statement that the new Mac was "2x faster" was wrong because they got smaller speedups. What this article s howed is that if you used Macworld's methodology (showing benchmark results without showing processor usage) you could argue that the quad-core G5 is only 14% faster than the Intel iMac running Quicktime. They're not saying that such a conclusion is correct, they're using it as an example to show what conclusions you can arrive at if you use Macworld's logic.
The basic problem was that Macworld's benchmarks were not CPU benchmarks and didn't make full use of the second core in the Intel Mac. The '2x' number Apple said was for the CPU --- even SJ mentioned that it doesn't mean apps will be 2x faster since the disks and everything else are the same. This article shows that in cases where the benchmark is CPU bound, the new Intel Mac can be almost twice as fast.
A deep unwavering belief is a sure sign you're missing something...
Its referring to tests that don't max out the CPU anyway, and therefore presumably have bottlenecks in some other part of the system. Here's a more rediculous example using the same theory:
Test: Compressing and sending a 16MB file over the network
iMac: 83 seconds (cpu usage 23%)
quad: 84 seconds (cpu usage 11%)
Wow! The iMac is faster than the quad! Of course, in reality it was working much harder to accomplish the same task (compressing at a bandwidth-limited speed). The articles point - and it is very poorly written, I will agree - is that this kind of test is crap.
The Macworld test used the same theories in the other direction. After all, if you perform a task that takes the old G5 iMac 20 seconds but uses 99% of its CPU, and takes the new intel iMac 19 seconds but only uses 45% of its total CPU power, I think you'd say that the iMac was more than 5% more powerful, right?
Admittedly if all you ever do is one task at a time, you wouldn't notice the difference. Considering that many people like to do multiple tasks - watching the recent keynote in a background window while doing some other work in a foreground window, for example - this is not an inconsequential point.
That brings up the example from the linked MacSpeedZone article:
Encoding one QuickTime movie:
intel dual core iMac: 97.02 seconds (87% CPU)
g5 quad core powermac: 84.85 seconds (42% CPU)
advantage g5: 14% faster
Encoding two QuickTime movies:
intel dual core iMac: 176.60 seconds (100% CPU)
g5 quad core powermac: 86.25 seconds (87% CPU)
advantage g5: 105% faster
Even that's a little misleading, since the quad still had spare processor bandwidth. This is why a lot of benchmark tests are designed to test each piece separately, spinning them up to 100%. Of course, real world tests are great as well - but only if your usage actually parallels those tests.
You're special forces then? That's great! I just love your olympics!
OK, lots of talk about these but here it is from someone with both G5 and Intel iMac 20" machines. For some things the Intel is faster than the G5 by a significant margin (Safari in particular feels quite snappy) but when you have to run PPC apps the G5 is much better. For the moment there are really quite a lot of apps that are not Intel native so the overall impression when using the two machines is that the Intel is no quicker, and some times much much slower. For PPC apps the Intel machine is no better than my 933Mhz iBook G4. Worse, there is significant pain at the moment in doing much that is taken for granted with the G5 iMac. Many programs do not run (we use BlueJ and Eclipse, neither work on the Intel). You still get the spinning beachball of death, and it seems quite often too. All in all, it feels just like any other previous Mac.
One thing that impressed me was the fact that Rosetta is able to run command line apps compiled for PPC. Gives a good idea of just how fast Rosetta is when running raw PPC code without a GUI. The answer is that a 2Ghz Intel chip running PPC code is about the same speed as a 500Mhz PPC. very reasonable compared with something like PearPC but still a significant drain. You get some back with the GUI as much of that code is native so something like MS Office actually feels usable. Our 2.3Ghz G5 Xserves smoke both the G5 iMac and the Intel even when the Intel is running native code at least with our apps.
So, do I recommend the Intel iMac? Probably. Would I recommend against a G5? Nope. Buy whichever you like. With the G5, you know what you are getting and it will still run software for the forseeable future. The Intel machine is pretty hard work at the moment but has the promise of getting better as more universal apps come along. Of course, there is currently no viable fast PC emulator so you can't run Windows or Linux on it. With Qemu or VPC on the G5 you can run Windows quite reasonably but not as quickly as you will be able to in say, six months when MS get off their arses and build VPC for the Intel Mac.
I can see why Apple released the iMac first, makes sense. The G5 iMac was never really a speed demon so the Intel one doesn't suffer too much overall. Same goes for the MacBook Pro which should be able to keep up with the G4 PowerBooks. It will take a while yet before slotting an Intel chip into the pro towers makes sense though.
A Mac is a Mac though, doesn't really matter what is inside chip wise.
"I have the attention span of a strobe lit goldfish, please get to the point quickly!"