Help me figure it out !!!!! (gtx 750ti asus p8z77-m compatibility)

I decided to put a new video card because the amd 4600hd is outdated, I chose the GeForce GTX750 Ti ASUS STRIX OC PCI-E 2048Mb and saw it with a pci-e 3.0 connector and I have a pci-e 2.0 on my motherboard will my motherboard be compatible with the video card and if so, what is the difference? (computer percent intel core i3 motherboard asus p8z77-m video card GeForce GTX750 Ti ASUS STRIX OC PCI-E 2048Mb).