看来遇到一个专家了。接着支招！

It is no problem if My PC DVI using DVI to VGA adapter then connect LCD VGA input. The problem is directly PC DVI-D to LCD HDMI connection.
Thank you so much for your suggestion about the high capacity HD. I only give 150GB for record TV shows with recurrent mode. My PC power supply only 350W. If I want to install a big HD, do I also need to change a high power supply? It is hard to find a quite power supply. quite is the key. Do you have any recommendation?

My on board audio card support 7.1. However, Logitech Z 5500 Digital system is the only one I can find high as 5.1. That is the reason I bought it. You should write a article to us amateur on how to configuration a PC TV, not me.

I am not sure why do you think I need a high video card? I could not find any different if I use 64MB video card. Could you please explain? By the way, I do not play game.

Thank you so much for your help. It is so good to have a 专家指点。