Hi Tanda...
The difference is that the GD model has the HDTV tuner built-in. That's it.
While both models are capable of displaying high-definition content, the G model will require a separate HD Tuner to watch HDTV.
This does NOT affect DVD viewing however.
Hope that helps.
J
I am looking to purchase one of these & realize the G4U has the AVS box where the GD4U doesn't. I plan to hang on the wall. The fella at my local Tweeter store says I don't need the AVS box because I am only plugging in video only. I notice when I check prices the GD4U is higher priced by $300 or so (internet). Why is that? I would think it would be less money since it doesn't have the box. Do I need that box or can I get away without it? I have a DVD and VCR that I will be hooking in to the t.v. Any help on this would be appreciated.

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