It wouldn't matter at all if it had PCI 1.0, 2.0, or 3.0 slots. The difference between each is so small you would never notice. This shouldn't concern you the slightest. What you should concern is how good your other components are, so that you do not get any bottleneck in your computer.
Looking at your motherboard, it looks like PCI 2.0.
However, like I said. It shouldn't matter. Make sure your processor is quad core, at least 3.0 ghz. 500 Watt power supply. Not sure what other tips I can provide because I don't know the purpose of your computer.
Anything else I can help you with?