Unless you have a particular need for two network connections you can drop the separate PCI card as the motherboard has a 10/100/1000 card built in. I would wait with the soundcard as well until you've tried the onboard. It's likely it will be sufficient. I'd be tempted to get an SSD of 60-120GB (depending on what you can afford) for the OS with a 500GB HDD for storage if 1TB isn't required at the moment. Capacity can always be added at a later date. More RAM would be better, but that's dependant on you having a 64-bit OS which you haven't mentioned.
