I want to get a new GPU, and I was thinking about something along these lines...Gigabyte Radeon HD 7770 1GB GDDR5 DX11 DVI HDMI 2xMiniDP PCI-E
This card requires PCIe 3.0
My motherboard is, pretty old. http://www.asus.com/Motherboards/Intel_Socket_775/P5K/#specifications
On that page it says my mobo has PCIe x16. But I can't really make the distinction between what I need and what I have. Does PCIe x16 answer the 3.0 version which the GPU needs? In other, simple and plain words - Will this GPU be compatible with my mobo?
Regarding power supply, I have a 500w PSU, and the card GPU needs 450w, so I am covered there. Any help will be appreciated on the matter.