I have a Panasonic TX-32LZD85. Until recently I've been connecting my Windows 7 Ultimate PC to it with a VGA cable without problems. The last week, however, I haven't been able to get a picture on the TV from the PC. I've tried connecting using my monitor cable and had the same problem, so it's not the cable. The TV works fine otherwise. Please can someone suggest what I can do to view my PC on my TV again?