Graphics Card Between PCI 2.0 and 3.0 Explained
A couple of weeks ago a client of mine wanted to update the graphics card to his computer which will allow him to play the latest games, but first I had to do some research about the difference between PCI 2.0 and 3.0 compatibility. The computer was a Dell Inspiron 580 with windows 7 home premium 64bits and a total of 8G of ram which is a pretty decent system, although the mother board can take up to 16G of ram, you need to have windows 7 Professional, Enterprise or Ultimate to access it.
When he bought the computer it came with a video card ATI Radeon HD 5450 and 1024MB of ram connected to a PCIe x16 v2.0 from the factory which is not one of the best graphics card. One of the problems that I had was that the latest and more advance video cards are PCIe x16 v3.0 and what I found out is that basically all graphics cards are backwards compatible, now it might not run to its full potential, but you can still plug a pci 3.0 graphics card to a pci 2.0 slot on a mother board and it will work just fine.
Keeping in mind the difference between PCI 2.0 and 3.0 I decided to buy one of the best graphics card he could afford, the Geforce GTX 650 Ti SSC which came with 2G of ram which is a very powerful card at a very good price, another thing to keep in mind when buying a new graphics card is to make sure you have enough space inside the computer to accommodate the new graphics card, since they vary in sizes, the GTX 650 Ti basically takes two spaces, so if you have another slot next to the PCIe you will no longer be able to use that slot and also make sure you that your power supply can handle the load and depending on the card you get you will need an additional 6 pin power connector coming from the power supply to connect to the graphics card which in my case I had to replace the stock power supply.
Now for power supplies the higher the wattage the more stable the system is; so I put a 700 watts Thermaltake power supply which can easily handle anything you throw at it.
So as long as you have a PCI express slot available on your motherboard v3.0, v2.0 or v1.0 you can plug any graphics card you like, because they are all backwards compatible, just like usb, so the only difference between PCI 2.0 and 3.0 is that the most advance graphics card may run slower on a 2.0 slot.