what is the different between 6800 and 6800GT PCI-E?

[loco21]

I'm going to buy a video card and I have the money to buy the gt but I wan to know the different be side price on those 2 card and if worth the prices.

thanks in advance.

PS: Sorry if this question is been ask before but I din't find no info or tread availeble in the forum thanks again.