[Hipplewm]

I currently have a 667Mhz dual dual core 3.0Ghz Xeon machine

What is the limiting factor on the cards?

I know the bus multipliers? only one 16X, but I think another can be 8X.... I know where to look it up, but don't know the info off hand.

I replaced the X1900XT with a 3870, I am running a 30" and 23" cinema display.

Can I take the extender off of the X1900 and put it in another slot and buy the extra power cord and run it also? What about 2 3870's? What about a 4870 and my current 3870? (I have heard the 4870 uses both power slots...but can't verify)

Do we have an idea of what card can saturate a 8X bus? 16X bus? Meaning with a 3870 and my X1900 am I going to be saturating my PCI bus to the point that a 4870/3870 combo will be no faster no matter what?

General uses: FCP (Hobby), Photoshop (Hobby) Aperture (Hobby) WoW (3-4 accounts open simultaneously, if I can get enough screens) and that is about all the is major taxing, I play Quake, C&C and CoD, but only single screen.

Thanks for your help.

[SierraDragon]

The short answer is that mix-and-matching graphics cards seldom if ever works well on Mac Pros. Just install your single strongest card (or 2 identical of your strongest card) and sell the rest.

-Allen Wicks