My RaspberryPi suddenly stopped booting. When I power it on, green LED turns on for a second or two, but then nothing happens (nothing on screen - says "No input signal", nothing on serial port). I tried several SD cards that used to work with it, and I tried two different power supplies (Nokia 1.2A, Logitech 1A, both of which used to work with Pi), and nothing changes.
SD cards are being read, because if I remove start.elf, the green LED starts blinking 3 times every few seconds when I power it on. Any ideas what could be wrong, or what else I should try?
My Raspberry Pi is one of the older Model B's with 256MB RAM.