Well the PCI Express is the type of interface for graphics that your motherboard uses.
It is currently the top of the line interface for new video cards, being a step up from the slowly becoming obsolete AGP interface cards.
This basically means that the card fits into a PCI Express slot on the motherboard. The x16 is basically the speed of transfer between the the card and the motherboard. AGP used x4 and x8. I don't know the exact specifics of the x16 rating, but this is a general overall answer.
This post has been edited by Neela: May 10 2006, 05:56 AM
Yes, I think PCI-E x16 is the fastest graphics card interface available now (on normal computers), so it's probably good. I recently bought a high-end graphics card (ATI X1900XTX), and it's also using PCI-E x16.
I have no good knowledge of your graphics card in general, though. Maybe others can answer that, or you could do a google.
PCI Express is the highest end port. AGP is still alive, sort of, but everyone is moving to PCI-Express.
The high end cards are now only on PCI Express. And they went back and put a lot of the low end. Video cards only go into the X16 slot, the other ones are for different things, some motherboards support SLI, which means you can get two video cards and hook them up. ATIs is crossfire, which is basically the same thing.
If you have a PCI Express video card, you know you are doing well.