It can be done, just question of time and resources.
.....Conclusion:
Upgrade is technically possible, but doesn't make sense from financial point of view in my opinion.
@stachu: since my total ignorance on technical stuff, and seeing how skilled you are, amongst/together/among with other members here as well (it seems that the "elite" of Amiga technicians/hackers/modders/experts gather all together here in this forum as well as on EAB) i was wondering how factible would be (if possible, of course) to "upgrade" these cards to produce G4 accelerators).
Why i ask this? well, last night i was reading one issue of Amiga Format, and one ad (Gordon Harwood), was claiming "latest G4 accelerators from phase 5 are coming soon".
I think just before phase 5 went bankrupt, they were producing (i dont know on which stage they were at that moment) these accelerators, the "next gen" accelerators for Amiga at that time (1999/2000).
Dont know if the circuits are available, dont know copyright issues (DCE?), dont know how difficultl/different are G4 from actual PPC cards, how viable would this be ($$$ speaking), but...imagine an ideal situation: G4 accel designs are with no copyright/easy to get/easy to build/reverse engineering. A bunch of the most talented guys from this forum join forces to produce a batch of this. For sure, there would be many Amiga users interested in this upgrade (myself included).
I would prefer 100000 times this kind of upgrade than buying a "new Amiga", or an efika, or any other thing like that.
It will bring even more power to the Amiga, regardless somebody (i know they will) claiming "old stuff, non sense upgrade, etc).
From my humble point of view, if this is possible to do and doesnt cost 10000 euros each card, it would be a winner and would bring more fresh breath to the platform
Just my toughts. If they are totally out of this earth...excuse my ignorance.
. Dreaming is yet free...
and if this discussion has been, erm, discussed long time ago...again apologies..
Maybe in that time it was not viable, maybe now G4 chips are cheaper...i dont know..wish i had the skills to do that..but you have my full support if that counts
Sebastian