the same thing happened to me on Sunday i normally leave my PC Running all the time but on Saturday night i decided to turn it off to give it a rest lol on Sunday morning i turned it back on and nothing scratched my head and decided to investigate then i saw smoke coming from the back,i think the power supply has given up
so i dug out an OLD Packard and bell imedia s3210 and man is it slow compared to my one that blew up as i built it myself AMD 5000+2.6 ghz Black edition overclocked to 3.4ghz and 8gig DDR2 ram, so i will have to put up with it till i can get a new power supply - and i used to think that 2ghz 2gig of ram was fast how times change