Yes, you can; with the right motherboard, the right drivers (which Nvidia doesn't like to give out), and lots and lots of money. Don't forget a super large psu to power it all.
Question, why do you need that much graphics power? Most monitors can't use all that power, not even two monitors. Besides, a in few weeks, DX10 cards are going to start coming out, and in January, Vista might be released. Or will that be Easter? Not sure when it comes to Microsoft. Of course, you could run rc1 or rc2 and use the new card, I suppose.
Point is, spending that much money on DX9 cards right now is senseless, unless you're very rich and can afford to toss money to the wind.