| Onboard shit usually taxes your CPU...so if you don't have a power-house chip it could cause issues. It's best to get away from that as soon as you can. You can get a NIC really cheap on eBay, that's not a big problem. Also, you could probably upgrade that onboard sound to a SB Live(4-5 years old now), just something to take the sound processing load off of the cpu.
I've had issues since the 2.0 patch, so I believe that an upgrade might be in order for a lot of us =( | 