Sorry, ASUS M/B i'm not too sure.... using Gigabyte now.... If
your ASUS M/B is the Intel 775 type, there is only 1 IDE port. Yor
CD/DvD rom will have no place to put. I use SATA 2 HDD while my DvD
writer + DvD rom use the IDE.
Yes, if your M/B support SLI, then you can use 2 graphic card.....
but expensive lah...... the cards you listed can't support DirectX
10, therefore even if your SLI is good, can't really use for Window
Vista games. Suggest like me, just get a mid range or slightly
better card to use for next 9-12 mths, then upgrade to a DirectX 10
card and use window Vista..... 9-12 mths should be enough for
Microsoft to solve most of the bugs on Vista.
7600GS & 7600GT
GS stands for the lowest range of the 7600 serise
cards
GT stands for higher end ones....
Example - lowest to highest
7600GS - 7600 - 7600GT - 7600GTX
As far as i know, GTX is the best.......
Check out my POST here under 'My new PC' to see my new PCs
confing..... 
