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If you go to the apple store and select the DP867, then you can upg the video card to the GF4Ti, so for this reason I don't think you'd have any problem adding it to your machine.

[edit]
Oooooops! Sorry. I just re-read your post and noticed you didn't say it was the DP867, ignore what I have said above, sorry....:eek:
 
You should have no problem at all. I have the same computer and have been thinking about a gf4 TI as well. I just have not found anything that my geforce 3 could not handle at the moment to justify it.
 
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