I cannot get video from my TV when connected via HDMI. I get sound. It used to work fine, but I had to unistall and re-intsall windows. I used to have 8 but i only got 7 re-installed, maybe that is part of the issue?
Try updating your video drivers as well as your display drivers. Since you just reinstalled all info to the system, you may be able to get away with just disconnecting the TV, restarting the computer and then reconnecting the TV. Your computer may well say it needs drivers or other updates when connecting the new device.