1. If your TV also has VGA or DVI, try that...
2. If nothing changes yet, and if you have a Graphics Card installed, remove it temporarily.
3. If nothing yet, reset the BIOS
http://www.wikihow.com/Reset-Your-BIOS
4. If nothing yet, is your monitor older? try a newer one.
5. Nothing yet? Read the threads with different solutions for similar HDMI->TV setup issues... one of the answers there may have your solution.
http://www.tomshardware.com/forum/328010-30-bios-screen-blank-screen
http://www.tomshardware.com/answers/id-2211485/bios-hdmi-output-video-card-vga.html
6. Nothing there helped?.. Try using a Bootable CD/DVD disk with a Linux distro, Repair disk or Bootable antivirus disk. The BIOS post...