Question about SLI Build

[sadpony]

I already have a pc that I built and I am running with 1 video card. I have never used SLI before but I am thinking about picking up another of the same card for cheap, but before I do I want to make sure it will work on my setup.

Here is my mobo: Amazon.com: Gigabyte GA-Z68M-D2H LGA 1155 Intel Z68 HDMI SATA 6Gb/s Micro ATX Intel Motherboard: Electronics

Here is my video card: Amazon.com: EVGA GeForce GTX 550 Ti 2048 MB GDDR5 PCI Express 2.0 2DVI/Mini-HDMI SLI Ready Graphics Card, 02G-P3-1559-KR: Computers & Accessories

Here is my PSU: Newegg.com - CORSAIR Builder Series CX500 500W ATX12V v2.3 80 PLUS BRONZE Certified Active PFC Power Supply

Also have 8gb ram and a 3.3 Sandy Bridge Processor and an ssd for the OS.

Thanks

 

[*= WildCat =*]

Quote from manufacture

Expansion Slots 1 x PCI Express x16 slot, running at x16 (PCIEX16)
* For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
1 x PCI Express x16 slot, running at x4 (PCIEX4)
2 x PCI Express x1 slots
(All PCI Express slots conform to PCI Express 2.0 standard.)
Multi-Graphics Technology Support for AMD CrossFireXâ„¢ technology
The PCIEX16 slot operates at up to x4 mode when AMD CrossFireXâ„¢ is enabled.