The 750fx...
...is/is not the following things:
1) It is not the G5. It's a G3. A fast, low power, bus speed boosted G3, but still a G3.
2) It will not and cannot outperform a current top-of-the-line G4. G3s can't be multiprocessor, don't have Altivec, don't have a level 3 cache, and don't have as advanced an FP unit. The only advantage it has is a bit more L2 cache and a slightly faster bus.
3) It does not have Altivec, nor anything like Altivec. Also, it would be a horrendous waste of die space to make the entire chip SIMD capable, it would mean that half the chip wouldn't be being used most of the time, which would make it slower than it would be without SIMD.
4) It is the ideal chip for the iBook. 1GHz, 200MHz bus, 512k L2 cache, 3.6 watts.
The IBM alternative to a Motorola G5 can be seen by looking at their PPC roadmap (
http://www-3.ibm.com/chips/products/powerpc/rdmap/roadmap_small.jpg ). It's multi-core (2 or more chips in one), 1GHz+, integrated SIMD (read that as Altivec/SSE/3dNOW! clone), probably with DDR support, .13 micron, SOI, probably with PCI-X support, probably some other stuff. They
are working on it, but there is no reason to believe that it's the G5 rather than the MPC7500.
Also, AMD does
not emulate x86. Their processors are pure x86, even their new Hammer chip (it's a 64 bit extension to x86). I believe you're thinking of Transmeta, which makes a VLIW processor that emulates x86 in an extremely nifty way and runs on only 1 watt of power. They could easily make it emulate PPC instead. If Transmeta makes a high performance, PPC/x86 compatible chip, and Apple uses it, I will be very happy. Code morphing is awesome(the tech they use to emulate x86).
SSE/SSE2/MMX/3dNOW!/Enhanced 3dNOW! all
try to do what Altivec does (which is add a dedicated SIMD unit to the chip). However, they suck at it. If the P4/AthlonXP had something as good as Altivec three things would be true:
1) The chip would require the best heat sink ever made (they're already hot, adding *four* pipelines and 32 128-bit registers would just make them bigger/more power hungy/hotter.
2) The extra space would make them more expensive
3) The G4 would be doomed. Altivec is only thing that lets it get anywhere close to holding its own against an AthlonXP 2000+ or P4 2.2GHz. If they had Altivec they would blow it out of the water.
