help selecting 5.1 surround speakers



Hi I'm about to buy a set of 5.1 PC speakers for use mainly for gaming.

I need help selecting the best one to go for as I have no idea what to look for in this area. I've got £100 to spend.

Also I don't own a soundcard since I use the onboard audio ouputs on my ABIT AV8 mainboard. Is the onboard audio capable to produce 5.1 surround sound?

Thanks for your help.