Question regarding Windows 7 and SLI

[aliasxneo]

Hello,

I recently purchased a second GTX 580 and am looking to place it in a SLI configuration with my current system. I was instructed that when I do connect it, I must re-install Windows 7 for it to work properly. Is this true? Furthermore, am I able to backup my current Windows 7 and then re-install and restore from the backup whilst still keeping the new changes from SLI being configured?

Really, I'm just looking for the best way to go about this without having to re-install my whole system.

 

[aliasxneo]

You can add the card without a re-install.
However if there is issues i would re-install your drivers.

Alright, I figured that was the case, just wanted to verify though. Thanks.