1. 50/50 chance you'll plug the floppy in backwards. If the light stays on when you power up, unplug and turn it around. 2. Do NOT skimp on a PSU, quality wise or power wise, it is the beating heart of your build. Underpowered PSU's seem to cause more problems than anything else and a cheap $30 PSU can be disastrous. You can get a very good PSU for $85-$110 that will see you through upgrades, provide smooth power and won't blow up. Buy more power than you need but not too much, remember that all PSU's have a sweetspot where they work the best. Add up all your components needs, then but 30%-50% more than that (convenient calculator http://www.jscustompcs.com/power_supply/ ). You won't be sorry. Also, the newer Mobos are really power hungry and most use 24 pins. 3. As stated before, research is the key and it is also really nice to have a functioning PC hooked up to the internet for troubleshooting. building disks etc. while you are building your new baby.