Adding an additional graphics card to my Vista setup

Hey, my first post here after being recommended by Hexus Member Howard :)

I currently have a ASUS P5W DH Deluxe motherboard which features "Crossfire" support which therefore means it has two PCI Express slots. I currently run just a single Sapphire X1950Pro in the top slot of the PCI Express Slots. (I went for this card as it was only £95 and will keep my Pc going till ATI release there next DX10 cards).

I run a dual monitor setup with two iiyama Prolite's using the two DVI outputs on my cards. I understand having two monitors usings up more GPU resources therefore I turn off the second one whenever I am about to game (except in Supreme Commandor which supports dual monitors :D).

I have looked on ebuyer and found various cheap PCI express graphics cards for around £30 which I would like to add to the second PCI Express video slot, but NOT in any form of Crossfire solution. Basically I have a big samsung LCD TV connected to my Xbox 360 which I use for HD-DVD playback and HD gaming but I wanted to connect my PC to it for when I play back H.264/x264 content available on the internet.

Basically my idea is to connect both my second PC monitor AND my LCD tv to the second card, meaning I can have all three monitors supported, and all the performance out of the x1950 will all go into the one single primary monitor for my gaming needs.

What I hope to acheive is to still be able to use Aero in my Vista Ultimate x64 OS. And at the same time have both my second monitor plugged in and my tv plugged in. My idea of leaving just the primary monitor on my monster of a card was so that I can leave my 2nd and 3rd monitor on without taking a performance hit graphically.

Is this possible at all, I heard a lot about mixing graphics cards stops Aero from working. Also how would the PC decide what graphics card is primary?


Many thanks for any advice you can offer :)