I am buying a new system, and have received great advice form this community about my power requirements, and system compatibility. The questions I now have concern the difference between modular and non-modular Psu's, what is the difference and which is better? Will a non-modular psu fit in a mid-tower case or should I go for the more expensive high wattage modular psu's? Please just answer my few questions fully so that I can know the difference too. I thank you all in advance-Bobby the second.(My dad says that no-modular psu's don't fit in mid-tower chassis, i doubt this, but is it true?)