I have been asked a question that I can't answer, but I think I know the answer...
My friend wants to span his G4 iMac to the screen of his G3 iMac... I have never heard this question before. Perhaps because I thought it was a no brainer, My first response was NO WAY... But I told him that I would ask people in the know...
I know about the hack to get a 2nd "monitor" to span, but not an AIO with limited inputs....
In principle, you could probably construct an adapter to fit the internal ribbon cable which connects the AIO monitor to the A/V board which would adapt it to VGA. It's probably been done before. (By someone upgrading an AIO with a faster video card.)
But... it scarcely seems worth the trouble, really. The AIO's monitor isn't that great. (1024x768@70hz, tops.) A better 17" or 19" monitor goes for barely over $100 these days.
Ahh, I tried to edit my post, but couldn't find a way... AIO meant: all in one form factor G3 iMac... I have an AIO and understand your comments all too well, as I have contemplated hacking it's rather weak video... I was thinking iMac G3, Small weird little box that it is.
Well, in theory you could apply the same principle, but with a few extra wrinkles. The monitor in the iMac G3s is, well, weird, in that it's not really a multiscanning VGA monitor. It operates at a fixed horizontal refresh rate, so it won't sync precisely with any of the "VESA" standard video modes.
(Just from memory, its modes are something like the following:
In theory it should be possible to drive said monitor from most VGA cards, (Or a new iMac's video output), but it might take some tweaking to convince the video drivers to output a mode it likes.
The big problem that you're going to run into is that, even if you get the second iMac to input video properly, is that the G4 iMacs (well, for that matter, *any* iMacs) are incapable of monitor spanning. All the better you'll get it video mirroring.
At least the 17", 20" and lastest 15" ones can, with 'the' hack.
Check out http://www.rutemoeller.com/mp/ibook/supportlist_e.html
for the list of supported machines.
I've run it on my 700MHz iBook for several months - a 1280 x 1024 18" LCD alongside the iBook is just great for desktop use!
I understand your comments, but I am new to this whole idea, remember I asked this for a friend? Anyway, I Own a G3 iMac that has the monitor output port... So, are you saying that this output port can double as an input port? Would I have to hack a cable to make it work? or are there some out there? OR, are you speaking of an internal hack to get the video signal into the iMac G3? BTW: as stated later in posts, I am aware of the limitations of spanning on the G4 iMac, I was speaking of hacks I had read about, to make this possible...
The video port on the back of an iMac is output only. To use the monitor with another computer you'd have to open the machine and hack into the cable running between the motherboard and the monitor board.
Doing that would tend to imply that you no longer wanted to use the iMac as a stand-alone machine. ;^>