Wow, no chime, that's veeery bad! THat means the motherboard hadn't passed the self-check.
Have you done anything particular before the "death"? That's a problem that can't come out from nothing.
If you want you can try an EPROM reset, by doing what is written here --> http://support.apple.com/kb/HT1379
Try even disconnecting the mac from power supply and keeping the power button held for some seconds (10-15)