zenith lighting in Orlando Florida - have put together xserve macs with latest ones-
they managed to fit different graphics cards-
apparently the gt120 fits - but that doesnt perform too great ( though its better than internal card ) - particularily as they wanted to do at least 4 hd layers -
i think they got a 8800 to fit instead - but they had to solder power connections.
They did get help from apple trying to figure this out-
The guy who did it was prepared to do the hacking himself and take the risks...
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I also have a show in china at the moment using xserves - much better form factor for install
performance not critical on this show-