# Upgrading h/w for OSX - is more MHz better than dual G4s?



## brianleahy (Mar 8, 2001)

I'm currently using a G3/400 B&W.  

I'm considering a hardware upgrade.  My question is: in OSX (with it's multithreaded capabilities) will you get better performance from a 733Mhz single G4, or a 533Mhz dual G4?  There's a $1000 price difference...  but if OSX takes full advantage of both G4s, I'd expect that dual 533's would effectively give you nearly 1066Mhz...

How about a 533Mhz dual G4 vs. a 667MHz single G4?

And while we're at it:  How about a 450Mhz dual G4?  These can be had fairly inexpensively at a couple of online vendors. 

Anyone who has any insight into how much difference dual processors make - your input is appreciated.

-BL


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## endian (Mar 8, 2001)

I'd get the dual - even the 450. There are a bunch of stories floating around about how slow the 733 is.


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## jackd (Mar 8, 2001)

Obviously, no single thread will run as fast on a 533mHz processor as it will on a 733mHz processor. 

But overall system performance will be better on the dual processor machine.

You may or may not see this increase in individual programs-- few Mac applications are multithreaded. And whether you see any benefit at all depends on how heavily your system is loaded.

That said, I'd still go for the dual procs. I suspect you'll see a significant benefit when trying to do something while Classic is running...


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## AdmiralAK (Mar 8, 2001)

I heard a rumor that apple will not be supporting dual processors in OS X 1.0.
Whether this means it wont be able to use the 2nd processor period, or whether it will use it baddly I do not know (the article did not elaborate).

I would go with the 733Mhz machine since it does come with a DVD-R/CD-RW drive 


Admiral


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## zaustin (Mar 8, 2001)

I just wanna warn you guys about taking these early benchmarks to heart.  Just like the Pentium 4, the 733 G4+ WILL be the fastest single chip solution after recompilation becomes widespread.  Just a warning.


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## hELLO wORLD (Mar 9, 2001)

I think all depends on the importance of these 1000 $.

I you can afford such a difference, and this doesn't change your life, you can choose the 733 with Superdrive. Of course, if you don't need Superdrive, or saving 1000$ is important for you, just take the dual 533 !
533 single vs 733 is not such a difference, and dual 533 provide a very high performance. Better than single 733 on Mac OS X I think.
I have read that Mac OS X has a 80% (forgot the name) with MP. That means that a dual 533 can provide the same power than a single 850 MHz G4 ((533 + 533) x 80%)....


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## theed (Mar 9, 2001)

Most mac apps are very single threaded.  If you typically use one mac app very heavily, then you will feel like it has one processor all to itself in a dual environment.  The throughput of a single thread would be faster on a single 733, but that's not what feels so great about X on duals.  I compress a quicktime movie, and I see Qicktime hog up a processor all to itself.  I still use my computer and I don't feel it AT ALL!  Essentially all of my other requests go to the idle processor.  So theoretical throughput is better on a single processor, but the ability to run full speed background tasks as if they were on another machine, while still using your machine as hard as you normally do... priceless.

As for X not supporting duals, I'd have to say that's crap.  Process scheduling is so low level, they'd have to take things out of code they aren't updating to ruin multiprocessing.  They might not support 4 processors, but duallies are already done.  it's a mach thing. y'know?


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## brianleahy (Mar 9, 2001)

Truthfully, a 733, tasty though it is, is a little out of reach right now.  Mostly, I'm considering buying a Dual 450, because of the lower cost.  

Obviously, a dual G4/450 is going to be an improvement over my single G3/400, but I was curious about how dual procs stack up against a faster single proc.   I may decide to wait another year and save my money.

The Superdrive is neat, but honestly I can't justify the cost.  I have an external CDRW that I very rarely use - so it's a little hard to justify spending a lot of cash on a DVD-RW.


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## AdmiralAK (Mar 9, 2001)

IN the end it's up to you lol,
IN my opinion, apps have not been made so that they  can
take full advantage of 2 processors which is something
that is not going to change in the near future.  If apple
reintroduces the dual processor line and they become more
mainstream then you will see apps that can handle it better.

The OS can multitask, and use the 2 processors but most of the time you are not copying, deleting and movgin huge files around, most work is done in applications. so IMHO a single processor 566 or 633 might be better if you are looking at price as well (damn costs  )


Admiral


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## I_GOT_A_G4 (Mar 9, 2001)

Go with the 633. The dual processor only works with some applications so it is not like you get 1066ghz with teh deul 533. But in the end it is up to u.


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## strobe (Mar 11, 2001)

Unless Apple recently changed something, only the 633 and 733 G4s have two AltiVec units. The 533DP has one per CPU.


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## saffron (Mar 11, 2001)

Hi !

I think it really depends on the apps you use.
For example, Cinema 4D from Maxon takes full advantage of multiprocessing and reaches the speed of 180% (which is the highest possible) compared to a single processor.
Since I´m a C4D user, I definitely would take one of the MP-apples.

CU,
saffron


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## theed (Mar 11, 2001)

dual processors benefit ALL X native apps.  The benefits may not be a dobling of performance, but the nature of the API's in a premptive environment makes it possible to divide up tasks that are going on in the machine to different processors.  Only 9 based apps, and some 9 based carbon ports sit really heavy on just one processor.  Even then, underlying system tasks like drive and network access will utilize the other processor, so your speed improvement is still noticeable.

As for copying, deleting and renaming ffiles simultenaeously, that's done by the Desktop Application (an application) not the OS.  The OS merely provides multitasking, applications use it.  

Maybe I live in a different reality, but I keep an eye on my processors all the time, and I can't stand to go back and live in 9.  I totally recommend multiple processors, it allows for a more efficient and freeform workflow, and the speed is there.  It allows you to be in charge of the computer again, instead of the computer telling you how many things you can do at once.

Once you have two processors at once, you'll never go back.


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## saffron (Mar 11, 2001)

Yes ! Of course you are right, Theed. I almost forgot all I already read in our german "Macwelt". But C4D benefits also from multiprocessing without OS X, if the information from Maxon is right. With OS X: I don´t see any reason to buy a single processor.

CU,
Saffron


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## AdmiralAK (Mar 11, 2001)

Wo kann man "Macwelf" finden ????

(lol.. ok incase my german sux, where can one find macwelt ????  I want some extra (interesting) reading so that I can practice my german)

Danke 


Admiral


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## BenW (Mar 11, 2001)

Es ist aber ganz einfach...
http://www.macwelt.de (könntest auch http://www.yahoo.de benutz haben). 

 (and if my colloquial German has fallen below the standards of any of my fellow macheads, please don't let me know)

[edit: smilie was wrong!]


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## saffron (Mar 12, 2001)

Sehr gut, Ben!

Sogar als Deutscher habe ich keinen Fehler gefunden.
Man kann übrigens auch einfach einmal http://www.macweek.de ausprobieren. (Die sind bei den neuesten Nachrichten schneller als macwelt)
Sowieso: Einfach mal alles mit ".de" eingeben...

Gruß,
Saffron


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## AdmiralAK (Mar 12, 2001)

danke schn ;-)
Ich wird diese seiten suchen und lesen.
LOL...mein deutsch ist nicht sehr gut denn ich studiere die Sprache nut fr zwei Jahre 


Admiral


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## Pascal (Mar 12, 2001)

> _Originally posted by AdmiralAK _
> *In my opinion, apps have not been made so that they  can take full advantage of 2 processors which is something that is not going to change in the near future.  If apple reintroduces the dual processor line and they become more mainstream then you will see apps that can handle it better.*



This comment only applies to apps used in OS 9, but it _does not apply at all_ to anything that runs in OS X.

Indeed, in the new OS, apps are not "metal-aware" like they used to be in OS 9 (and they have no need to be). By  "not metal-aware", I mean that applications cannot directly see the kind and the number of processors available. All this power management is done by the OS in a maner that is completely opaque to them. This is great because programmers, from now on, will not have to bother about compiling apps for dual, quadruple or octuple (dream on  ) processors. Whatever the number of processor available, the OS will transparently dispatch the workload to any CPU available, on the fly, without the consent and the knowledge of the running app.

By the way, this means that if you have a dual processor Mac, runing classic apps in OS X will be much faster than in OS 9, because Classic will take advantage of both processors while OS 9 uses only one most of the time !  On a 533 MHz G4, using  *hELLO wORLD*'s calculations, it will be as if you suddenly had a 850 MHz G4 under Classic...

Alles ist gut !
(German seems to be _in_, these days !  )


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## jackd (Mar 12, 2001)

While it's true that apps don't need to do anything special to be dispatched to different processors by OS X, it's also true that the programmer can make apps use multiple processors more effectively by "threading" them-- that is, spinning off separate threads of execution.

For example, IE could handle downloads in a separate thread, which would make browsing while downloading's going on a lot snappier, especially on a multiprocessor system.

One of the things I like about the Be OS is that apps using the standard Be libraries get a lot of threads for free: all the UI stuff gets its own thread, for example. I'm pretty sure that OS X doesn't provide this degree of auto-threading...


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## Pascal (Mar 12, 2001)

> _Originally posted by jackd _
> *the programmer can make apps use multiple processors more effectively by "threading" them-- that is, spinning off separate threads of execution.*



I totally agree, but this good programming practice has nothing to do with the number of processor on board... Good modern programming practices suggests that one should always multi-thread...



> *One of the things I like about the Be OS is that apps using the standard Be libraries get a lot of threads for free: all the UI stuff gets its own thread, for example. I'm pretty sure that OS X doesn't provide this degree of auto-threading... *



I don't know about this, but I would guess that if it is only a matter of librairies, then this situation can be easily improved upon at a later date by updating the librairies... This will be easy to do since the librairy architecture (framework) in OS X is so adaptative.


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## Yeti (Mar 13, 2001)

I agree with many of the things said here, but as we have read many times Mhz is not everything. I have been working on an "old" PowerMac G4 500 (single processor) and I am really happy with this machine. It works fast and reliably. I have installed MacOS X and I think it makes the machine much more powerfull and faster than MacOS 9.x (with the final release of OS X it will be "really" noticeable).

Now I have tried one of those 733 new machines (with MacOS 9.x) and I have to say it seems a little bit faster, but that's all. What is the real performance upgrade in productivity you get when changing machines that are not so distant in the developement chain? A 10-15 percent?

Then I have tried one of the "old" PowerMac G4 500 MP (dual processor) and I have to say I go with it. The fact is I could find one at a bargain price and I think it is a much better option than a 733, specially in my case, that I will go with Mac OS X right away and I don't need a DVD burner.

BTW, anyone to practice Spanish?


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## Matrix Agent (Mar 13, 2001)

yo tengo algunas espanol en mi cabeza. el es muy pequeno. Thats problably all wrong, but its all in the name of stretching the boundaries of grammar : p


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## AdmiralAK (Mar 13, 2001)

First of all:
I second the motion that Mhz is not everything 

secondly:
Non conosco la lingia spagnola .... ma ... parlo uno pocissimo d'italiano .... LOL ...
Noi possiamo parlare in italiano ???  lol

ok enough with the practice (for now lol ... )

(Russian and japanese to follow next semester  .... greek and french always available, inquire within lol )


Admiral


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## Matrix Agent (Mar 13, 2001)

you would be surprised how similar spanish and italin are, i understood it all. or at least in my mind i did. now. german. thats a language you actually need to study for, thats why i take spanish.


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## Pascal (Mar 13, 2001)

Cest avec plaisir que je parlerais en français ! Qui veut jaser avec moi ? AdmiralAK, peut-être ?

C'est indéniable : ce forum est international ! Ce n'est plus un forum sur Mac OS X, c'est un forum des nations !


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## dani++ (Mar 14, 2001)

Well-written MacOS X drivers (and Darwin) run in their own threads in kernel space. That allows the drivers to take advantage of SMP seamlessly. You can see an example of a driver at http://www.darwinfo.com (or was it .org?) and the actual code that creates the thread.
<br>
<br>
So multi-processor boxes running MacOS X take advantage of their processors no matter what, even if they only run non MP-aware apps. Even downloading is incrementally speeded up (I mean, your additional CPU(s) won't sit there like ducks).
<br>
<br>
dani++


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## brianleahy (Mar 14, 2001)

When I get the cash together, I'm definitely going MP.

Thanks to everyone for the input.

-BL


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## AdmiralAK (Mar 14, 2001)

Multiprocessing machines are nice 
I wish apple had not discontinued them (at lest keep them going and not stop production even for a little while)


as for french...
pourquoi pas ?? mais mon français est terrible lol.. je n'ai pas parlé la langue pour... quatres ans!...

mais c'est une opportunite ;-)

Admiral


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