Are we missing something?

I don't know diddly about chips but what if the G5 is the G4 with more goodies. I don't see why that would change the coding for apps. That's like saying the G4 requires more coding then the G3.

Could be wrong tho

It won't change the coding that much at all. The G5 is still a PPC and being a PPC chip just doesn't mean it share the same name they share a common architecture. Every processor still has it's instruction set and that's what the Programmers are concerned with. Now moving from say a Motorola 68000 Series to a PPC 601 was a changes...lucky Apple wrote a decent emulator until Native apps came. No such probs with the G5...it's all fairly the same. OSX also does a better job Abstracting the HW from the SW. No SW can talk directly to the HW.

[quote]Originally posted by hmurchison:
<strong>\\OSX also does a better job Abstracting the HW from the SW. No SW can talk directly to the HW.</strong><hr></blockquote>

Except for device drivers.

The PPC instruction set guarantees a high degree of backward compatibility, but there are a few bumps. AltiVec is an obvious one, as far as compatibility with pre-G4 chips is concerned. Obviously, each chip will have a different implementation of the PPC instruction set, with different strengths and weaknesses, and possibly different instructions for optimizing performance (the G3, for instance, introduced a number of cache hinting instructions that were part of the explanation for its being wildly faster than the 604e). These differences will mostly bite assembly programmers and particularly optimized code.

Compilers have to be aware of those differences so that they can generate efficient code for a given processor, and applications that want to take advantage of a new processor have to be recompiled on the new compilers (this lag explains why the 7450 was initially a lot slower, clock for clock, then the 7410 - it was running code optimized for a different architecture). This is also why game ports tend to be a little sluggish on the Mac. Game code tends to be heavily optimized for the x86 architecture, and the tricks that work on that platform don't often work on the PPC (in fact, they can make code slower).

Assuming for the sake of argument that the G5 doesn't look a thing like any previous iteration of the PPC - hyperthreading, multiple cores, etc. - then it will probably do a competent job of running code meant for, say, a G3. But until that code is recompiled on a compiler that really knows how to exploit its strengths, it won't really be able to show off. Compare, for instance, the GeForce3: In reality, on the Mac side, it hasn't lived up to its release hype, because no matter how many specialized and powerful functions it has , there's no benefit gained if nothing takes advantage of them. Especially if the driver itself does not!

[ 01-11-2002: Message edited by: Amorph ]</p>

OS X already is optimized for the G5, that you can count on.

The hard part is coding for altivec, but based on what I've read, the G5's altivec unit will have only minor differences from the G4's. I'm not well versed in CPU technology so don't take my word for it, but I think as long as Motorola releases a tip-top compiler that is heavily optimized for the G5, things should be easy for developers (remember, Moto makes metroworks codewarrior).

G5 release is imminent. Hold onto your butts because the G5 powermac is gonna rock harder, by orders of magnitude, than any other Powermac ever sold. It's gonna be a monster.

Think about this little factoid: According to the Register, the G5 will use a 10-stage pipeline. Compare this to the Pentium 4's pipeline, which if I remember correctly is 20 stages. 20 stages vs. 10 stages, suggests that the G5 will be considerably more efficient than the Pentium 4, it will calculate many more instructions per clock cycle. And this 10 stage pipeline chip is going to be clocked to 1.6 GHz, upon it's introduction! A 1.6, or even 1.4 GHz G5 will totally mop the floor with the Pentium 4. Imagine how fast the G5 will be in a year or so, after Motorola has scaled it up to over 2 GHz....it's going to trample other CPUs mercilessly.

Damn I'm getting a woody just thinking about this...I've got to hit the bathroom, be back in 15 or 20 minutes.

[quote]Originally posted by Junkyard Dawg:
<strong>...that you can count on....

...don't take my word for it...</strong><hr></blockquote>


[...]

Apple could of let down alot of people if they went for a G-3 in the new iMac LCD but they didn't...They are right on the money this year.Even,the iBook recieved a bigger screen.
We will get a Super-Powerful PowerMac with all the
Bells and Whistles.Plus,with FinalCut Pro,LightWave,ElectricImage,PhotoShop,etc..It is going to Rock!!!A few weeks...a few months...it is just around the corner.So save up!It will have to look different from the QuickSilver.As to differentiate it.It is going to be a Monster....

A lot of people wanted a bigger screen on the iBook.