Re: looking to upgrade...
1.takeout the hdd off of my list if you don't need it.
2.what kind of PSU do you have and how many watts ? I recommend between 400-500 watts for your build to power everything on and to be on the safe side.
If you have a 400 watt PSU and hasn't given you any problems that will do for now.
3.Of course you can, that mobo will take pci-express 16 1.0 or 2.0 graphics cards check the mobo specs on newegg.com to be sure.
4.As sure as I am running this new phenom x3 on my system everthing should go smoothly, I checked that boards ratings so you shouldn't get a DOA, but there is that chance that something might not function right away.
Half of the people here that have gotten advice and built their own pc's have some good success stories other times not.
Really you just have to be willing to take a chance and besides that you should have a one year warranties from the manufacturers just in case you need something repaired. don't forget that tip!