when it comes to power usage im not that up to date i currently have a 250watt power supply that came with a plain jane case , im running a pentium duo core 3.0ghz processor 2 gigs of ram and a 256meg nvidia video card i saw a new case at best buy that came with a 500watt power supply how do i know if that kind of power would be right for what im running, would to much power blow my motherboard ? i was highly advised to up my power supply a friend was amazed my computer was running to begin with.