G3 vs G4

whitesaint

whitesaint

cocoa love
Okay, well all know that the G4 an execute a billion floating point operations per second. Well what about the G3? How many operations can it execute a second? The reason I ask because the G3 is soo amazingly slow compared to the G4. Thanks in advance.

-whitesaint
 
I got 256.3 megaflops on my PowerMac 8600/420 MHz G3. That seems pretty correct, because a G4 should be around 4 times faster than a G3 on floating point operations, it takes 4 32 bit chunks in a cycle, when a G3 takes only one.

I want a new mac! :( ;)
 
I don't know, what are you doing with your G3?

My G3 really doesn't feel slow. Okay, maybe when I make a movie with iMovie, or if I make mp3s with iTunes.

There are not so many apps that really take advantage of Altivec, at least not that I use.
And Mac OS X doesn't feel slow either, although so many people say it uses Altivec. But where should a OS use that? Disc-Access? ;)

If you think that OS X is slow on your G3, you should think about getting a faster hard drive. That really speeded things up for me.
 
OS X uses altivec in everything, the system, the finder and every application. It just helps do things I guess. Like the window minimizing to the dock I guess...
 
G4's are 4-8 times faster than G3's on floating point operations, in other words, large calculations, image processing etc, which makes the G4 overall a much faster processor than the G3.
 
The main reason I ask this question, is because I am writing a Cocoa App that is 5-8 times faster on a G4! It goes really really slow on my 500 Mhz 192 Ram iBook, then I throw it on a 667 TiBook and it's amazingly fast! What gives? I didn't optimize my app for the Velocity Engine.

The only thing I can think of is if the Cocoa Run time system is optimized for the Altivec. If this is the case, I am in Heaven! Does anyone think/know if the Cocoa Run time system is optimized for the G4?

Thanks.

-whitesaint
 
Originally posted by Tigger
And Mac OS X doesn't feel slow either, although so many people say it uses Altivec. But where should a OS use that? Disc-Access? ;)
Click to expand...

It's a good question. As most people know, Altivec speeds up floating point operations. Integer operations are handled by the Integer Unit (IU). Most operations (including disk access) are not floating point operations. However, many of the most CPU intensive things that OSX does (mostly graphical tasks) are floating point operations. I imagine that's where Altivec comes into play.

Beyond that, the G4's IU can handle 4 integer operations per clock cycle while the G3's IU can handle only three.

You're not going to find very many true experts on which parts of Aqua actually use Altivec because it's closed source. However, I doubt there is any shortage of idiots willing to pretend they know what they are doing.

Hopefully this helps,
Vanguard
 
I actually used to have a PowerMac G4 533, but I sold it on eBay because I couldn't tell much difference between that and my iBook 500, which is now my only comp. I honestly don't find it that bad at all .. maybe I'm missing out. :(
 
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