Onboard sound is fine man, unless you are just really anal about uber quality sound which most people wouldn't even notice.
The only thing about onboard sound though is it has a tendency to die a lot quicker than of course having a good sound card like the one you picked AND, sometimes, if it's a real intensive game meaning CPU and GPU intensive, then the sound can get choppy since the CPU is trying to process it all.
All in all if he picked out the sound card I'd say let him keep it since he chose it already, obviously has money and good taste in a quality card lol. Better to have it now than wait for onboard to die and then go with no sound until he can get the card.
LED's btw castro, are the things that are behind your power button that make it light up
Basically he's asking if you want to make your computer 'flashy'
EDIT: Well.....it's fairly easy. Just read the sticky at the top of the OC'ing thread....get familiar with it 100% and your motherboard, it's BIOS, and read any review you can about your motherboards overclockability and the CPU. Then take baby steps. Sure you might not overclock for like 4 months or so if you felt like it, but the point is you might want to down the road and it's real easy especially with all the folks here to help