Isn't that an awful lot of work to go through to upgrade a 333 Mhz PPC to a 400 Mhz PPC, guys?
Better video, but lower max. memory.
Except for the fact that the G3 can't run MorphOS (just as the Efika can't run MacOS), I don't really see the point of this one.
The point is that this is an Amiga forum and an Efika running MorphOS2.6 can run many Amiga applications and games, as well as MorphOS native software. Efika motherboards can still be purchased new for $99, and although limited to only 128mb RAM, are still usable and probably more enjoyable to Amiga users than any version of MacOS being run on a 333 to 400MHz G3 iMac.
I don't recommend the purchase of an Efika mobo when used 1.25GHz G4 eMac's, and G4 PowerMac towers of almost any speed above 400MHz can be found for the same or less money and will provide much better performance and in the case of the G4 PowerMac towers, better expandability too, but for anyone that already has an Efika, or anyone that can get one for very little money, putting it into a G3 iMac case can be an interesting project.
I did not finish my conversion before the AmiWest show and was actually seen during the show completely tearing my G3 iMac apart in an attempt to get it to turn the CRT on, without the Mac mobo being installed (unsuccessfully). I did find out that the design of the slot loading 400MHz G3 iMac is completely different than my model and much easier to take apart, and might be a better candidate for such a project. I am still going to complete my Efika>iMac conversion and will provide pictures of it as soon as it is completed.
P.S. Starting with version 2.5, MorphOS has included some improvements to memory management in low memory situations when a video card with at least 128mb of VRAM is detected. This helps the Efika's performance and helps avoid running out of memory in some situations.