I imagine that you meant to link to the AE3000 not the AE300...
You are correct that the Panasonic will take any number of different resolutions (see the owner's manual) and it will convert them to fill the screen.
But, it is always best to get a video card which can actually output the native resolution and can do it using HDMI/DVI. This is actually really inexpensive these days as you can get video cards which should be able to do this for under $100 pretty easily.
Something like this gives you HDMI directly and supports 1080p.http://www.newegg.com/Product/Product.aspx?Item=N82E16814141080
- Theater, whole house audio, and technology consultation during the build and installation process in the Washington, DC metropolitan area.