Computer help..

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Im do realy suck at computers, and this might even be a noobish quest.. but here goes.. ^^

My computer:
I7.930 4x 2.80ghz LGA 1366
MB1366 Gigabyte GA-X58A
DDR3-1600 Kingston 12gb HyberX ram
Nvidia GF GTX 480 , 1526MB DDR5
Win 7 ..

I use a Hp27" lcd Screen atm.. but have just order a second screen.. 23" Hp LED, for boxing.

My noobish Questing..
1: Will this do Multiboxing 10man ?
2: Is 1 Videocard okay eventho I use 2 screens ?
3: Is it worth upgrading to Geforce 580...?
Thats it.. ty for reading.

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