Did you check if there's a bootloader on your chip?
From the FAQ:
"Make sure there's a bootloader burned on the Atmega8 on your Arduino board. To check, connect an LED to pin 13 and reset the board. The LED should blink. If it doesn't, see the Bootloader page (Arduino Starter Kit kaufen [verschiedene Ausführungen]) for instructions on burning a bootloader to the board."