Setting up sli on pci-e 2.0 and 3.0

I built my computer not to long ago, and in the build I put in a gtx 660,

The thing is that my mother board only has 1 pci-e express slot, and another pci-2.

 

The graphics card said it was backwards compatible. 

 

I plan on getting another gtx 660 (not right now but somewhere along the road)

Is it possible to run sli even though the slots are different ? 

Will this damage my graphics cards ?

This is my mothere board (http://www.asus.com/Motherboards/P8Z77V_LX/)

 

If i want to run sli will i have to get a new motherboard with 2 pci-e 3.0 expansion slots?

 

"The thing is that my mother board only has 1 pci-e express slot, and another pci-2"


I wrote that wrong,

Meant to say that my motherboard only has 1 pci-e 2.0 and another 3.0 slot.

you have one pciex 16 running at x16 speed and one running at x4 speed (the .2 and .3 revershon of pcie dosent matter yet no card fully uses all of a pcie x16 v2 yet)

But its not going to be worth runing a sli card with one x4 and one x16 speed slot as this will push both cards to run at 4x speed instead of x16 speeds

Either get a better motherboard and sli, or sell your video card and get a better one. Those are the only real options for upgrading.

Thanks for the advice guys. 

 

Probably going to get a better video card rather than replace the whole motherboard. 

The 7990 will be out soon ;) Just something to think about.

Will be sure to look out for it :D