Mac Pro, Dual Quad-Core and Processor Usage


So I've been thinking about getting one of those new sexy Mac Pros with the Dual Quad-Core Xenons. But I find my self asking if I really need it. I'm curious just how the multiple cores will be used. Does a program have to specifically be able to take advantage of all 8 cores? Or are some programs written to take advantage of as many cores as possible? If the program has to be written to take advantage of the extra cores, will having 8 cores just make me able to run multiple programs with more success?

If I get one of these beautiful machines, I'm most likely going to end up breaking the cardinal rule of macs, and putting Vista 64-bit on bootcamp. I've got the same questions for this OS as well. I'm also curious if anyone here has done this and had any success.

Thanks in advance for your thoughts.


U.S.D.A. Prime
Yes, a program has to be written specifically to be "multi-threaded" for multiple CPU cores to have any beneficial effect. Most programs nowadays are written multi-threaded (the complex ones, anyway, like Final Cut Pro, etc.) so more cores equates to more processing power, and shorter wait times. So, yes, running multiple programs will be "smoother", in addition to most programs running quicker overall (since more cores can do more work simultaneously).

The specific number of cores used for a program is directly correlated to how many "threads" in the program can run simultaneously. For video editing, that can be a lot. For gaming, it can be very few. The operating system will run as many threads simultaneously as it can, up to the ceiling of how many cores it has vs. how many threads in the program can be run simultaneously. If a program, for example, ever only has two threads that can run simultaneously, then anything more than a dual-core processor will provide no benefit in that specific program (assuming the dual-core processor and the more-than-two-core processor are running at the same speed).

The same goes for Vista. Windows programs have to be specifically written to be multi-threaded to take advantage of multiple CPU cores. No different from Mac OS X.

For daily use, like email and web surfing with a tiny bit of Photoshopping and what-not, 8 cores is overkill for anyone but a professional. If you can afford it, and the saying "time is money" holds true for you, then yes, the more cores, the better. It's really a matter of what you need vs. how much you want to spend... do you plan on using this machine professionally, or casually?


I was pretty sure that was they way things were handled in a multi-core environment but I just wanted to be sure.

I'll be using this machine for personal use so I'll be running everything from games to Final Cut Pro and multiple instances of IntelliJ (IDE) when doing some work from home. I'm mainly interested in the new Mac Pros because I feel that they're extremely powerful for the money, and I can run both OS X and Vista/XP if I need to. I also feel like this machine will last me quite a long time. Hopefully I'm right about that.


In Geostationary Orbit
Just budget yourself over a few months. The key word is SAVE some money each month to set aside to lessen the bite of the cost. Plus don't buy extra RAM or hard drives from apple when you buy the Mac Pro. Apple charges WAY TO MUCH for the extra things. Just get those extra things at places like OWC or others.


Greetings, ElDiabloConCaca,

Your message answers most of my concerns as I prepare to upgrade from a G-4 667 (w/ a 1.8 GHZ accelerator card) to a Mac Pro 2.8.

I don't (yet anyway) do high end complex vid editing, and I don't even own a copy of Final Cut Pro; so the most difficult vid editing would be what iMovie and public domain helper programs would need to do. Web development is probably the most consistent processor-intensive work to be done.

I can do iMovie stuff on this G-4 667, some of the tasks give me time to go make coffee.

So, the question is, how much of a performance hit would I incur by getting the
"One 2.8GHZ Quad-Core Intel Xenon, vs. the
Two 2.8GHZ Quad-Core Intel Xenon ($500 more)?"

Thanks much, ElDiabloConCaca,

San Antonio, TX


U.S.D.A. Prime
Well, in terms of multi-core processors, it also means that the more cores you have, the more individual programs you can run without taking a performance hit.

If, say, iMovie uses 4 cores, and you have an 8-core machine, then you could also run some other programs that will utilize the 4 unused cores while iMovie is using the other cores -- providing a smoother operating experience over a single, quad-core machine.

I think the question to you is, "is the extra $500 worth a little more processing 'oomph'?" Do you typically run multiple programs? Are you doing a lot of video editing? Say iMovie can use 8 cores... is rendering scenes in (almost) half the time worth it to you? I mean, are you under time constraints frequently that would justify the extra 4 cores?

Also, keep in mind that a faster computer that renders iMovie films at the speed of light won't make you a better videographer or video editor. It will only do it faster.

Hey, and greetings from down the street! I'm in San Antonio, as well!


Hi ElDiabloConCaca,
Thanks much for replying. I rarely do batch processing in tandem with other processor intensive activities, and unless there are some hidden characteristic of the Two 2.8GHZ Quad-Core Intel Xenon vs the one, then it appears saving $500 is more important.

I do get my hands dirty (on a Macbook Pro) and run parallels with winblows XP in order to run 3 different IBM-only apps, but I don't anticipate running that in tandem with any batch processing on the Mac side.

If the only difference is speed, then it appears that other efficiencies, such as lots more RAM should outweigh what the G-4 667 is doing with 1.5 gigs of RAM.

I wonder if Apple provides an upgrade path to add a second 2.8GHZ Quad-Core Intel Xenon.

OFF TOPIC: I looked at your web site and some of the impressive portfolio stuff; I should contact you on it later on.



U.S.D.A. Prime
No, Apple doesn't provide an upgrade path for a second processor later on -- when you buy the single processor computer, you're pretty much stuck with one processor for the life of the machine. While it's theoretically possible to purchase the Xeon processor aftermarket, Apple doesn't sell the cooling system or the fans or the mounts or anything (you know -- basically all the required stuff) unless you're an Apple Authorized Repair Center (or have a good friend that works at one, and even then, it may be price-prohibitive). Lots of RAM will definitely help.

I think you'll be very impressed with the performance of the single-processor, quad-core machine.

Of course, you'd be completely blown away by the octo-core, dual-processor machine -- but $500 -- eh, may be worth it to some people, not so much for others.

Thanks for the kudos, and we can talk anytime!