Yeah, too bad the G3 and G5 both run the same code. The g5 just has extra instructions.
Theres a performance difference yes, but the arch. is close enough to remain in the power series...and the code is not radically different.
If you wanna argue G3 vs G5, I can assure you theres no individual kernels in OS X for different CPU styles... 64 bit however is another story.
Adding SSE3 to a Prescott didnt make it a "different" processor.....
Reading through this its far from what I mean, but it might due... I;m tired and trying to raid something in WoW at the same time
Ofcourse, you're going to get a radically different performance from each, one had to be completely revamped for multicore use! Letalone the massive price difference in yields...
EDIT: Its like comparing an AXP to an A64.
Yeah, one has a memory controller and IPC enhancements, but at the heart.... they are almost identical...
I think you confuse the ISA language the processor uses with the basic architecture that makes it work.
To put it simple, all desktop PC processors since the 8086 (except for Apple's own 680x0 or PPC procs) use the x86 ISA instruction set, yet you cannot say that an Athlon64 X2 processor is the same as a Intel 80286 processor. Even though both processors are designed to work on the x86 ISA, their architectures and basic functions, heat dissipation, power consumption and manufacturing process are radically different from one to the other.
To further illustrate my example, Intel didn't just add SSE3 instructions to the "Prescott" as you say, the very inner works from this processor vary a lot from the previous Pentium 4 "Northwood" generation: a longer pipeline, double the L2 cache, the new "SSE3" SIMD instructions you quote, a greater power consumption and almost twice the heat dissipation, even Intel's own IA64 instructions are included in the silicon, but disabled during production of the processor.
Likewise, you cannot say that this "Netburst" architecture based processor is the same as a "San Diego" Athlon processor, or a "Coppermine" Pentium 3, or a "Conroe" Core 2 Duo, even though all of the the previous processors mentioned are designed to work with the x86 ISA.
I hope this helps you clear your doubts