Difference between 2.0x16 and 2.1x16 on video cards?

[gougeface]

Hello, my topic pretty much the question so if anyone could explain I would appricite.

 

[julius 85]

From Wikipedia:

"PCI Express 2.1 supports a large proportion of the management, support, and troubleshooting systems planned to be fully implemented in PCI Express 3.0. But, the speed is the same as PCI Express 2.0."

All PCIe revisions are backwards and forwards compatible.