How to set up crossfire?

[TheHman]

Hello all, just need to know what or if I have to change any setting , driver or anything before, during or after to get my second graphics card to crossfire with the first card, both cards are same (xfx readon hd 7950 one being having one fan and the new one has two)?
Im bit of noob to pc building but built this with trail and error and reviews and careful budget.
System specs:
CPU - 8350 amd fx
Ram- 16gb coarsir vengeance
MB - Msi 970-46a
Psu- 1000 watt (overkill I know but got it cheap) can't remember the name with 4 6pin PCI-e leads
Hdd- 2tb seagate (nothing special)
Gpu- xfx 7950 (single dispersion)
OS- windows 7 64bit professional
All drivers are up to date

 

[Eduello]

Hello all, just need to know what or if I have to change any setting , driver or anything before, during or after to get my second graphics card to crossfire with the first card, both cards are same (xfx readon hd 7950 one being having one fan and the new one has two)?
Im bit of noob to pc building but built this with trail and error and reviews and careful budget.
System specs:
CPU - 8350 amd fx
Ram- 16gb coarsir vengeance
MB - Msi 970-46a
Psu- 1000 watt (overkill I know but got it cheap) can't remember the name with 4 6pin PCI-e leads
Hdd- 2tb seagate (nothing special)
Gpu- xfx 7950 (single dispersion)
OS- windows 7 64bit professional
All drivers are up to date

Nope just plug the other one in and connect them with the crossfire cable. And of course enable it in the catalyst control panel.