well a few things:
1.IEEE what? this is what IEEE is:
http://www.ieee.org/portal/site
Unless that is the one IEEE standard to rule them all you need to be more specific like IEEE 1394 aka firewire or IEEE 802.11b
2 Why waste money on a card like PhysiX when there is no industry support yet. Wait t see if the card will be accepted and games use it or it will be a $250 paper weight. Same goes for the NIC, why do you need one? All new top end mobos have excellent onboard ethernet.
3. Forget the triple monitor gaming, its a mess. Want huge rez/size get a 30" 2500x1600 rez like the 3007wfp or the 30"apple display
4. Its not a tower that has limited slots (unless a very small one) its the mobo
5. The standard you mentioned was a long-dead attempt by Alienware to create a multiple GPU setup. It has been long killed by SLI and Crossfire
If you want to run huge rezolutions with very demanding games with everything up you'll need a 8800GTX or if you want to be uber hardcore 2 of them in SLI. That will achieve what you want and use the 2 cards to render different parts of the screen. But last time I checked while SLI is enabled you cannot run 3d images over multiple screens, quite sure its the same for crossfire.
So again your best option if you want high rez is to run 1 big screen like a 24" 1900x1200 or the 30" 2500x1600