Does my motherboard intel DG31PR have PCI-E 2.0 16x?

i want to buy a "EVGA GeForce GTX 550 Ti Superclocked" and add it to my motherboard...will it work on my rig.? im currently using 450w power supply do i need to change it too? my motherboard is mentioned above...it's a pci express 1.

here is a link of the vga..

http://www.evga.com/products/moreInfo.asp?pn=01G-P3-155...

i also have a noob CRT bt that wouldn't be a problem right? (viewsonic e71f ,monitor)



Manufacturer:
INTEL
Processor:
Intel(R) Core(TM)2 Duo CPU E8400 @ 3.00GHz (2 CPUs), ~3.0GHz
Memory:
4096MB RAM
Hard Drive:
500 GB Total
Video Card:
Intel(R) G33/G31 Express Chipset Family (Microsoft Corporation - WDDM 1.0)
Monitor:
Generic PnP Monitor (viewsonic e71f)
Sound Card:
Speakers (High Definition Audio Device)