Yeah. The only difference is the name and the price. If it's worth $30 to say you have a 9 series then it's the same. Haha.
http://www.gpureview.com/show_cards.php?card1=544&card2=575
Well yeah but it's kinda pointless to do 3-way SLI on 9800's. The third card would only increase performance by about 10%. Would be better to get 2 better cards for the same money. Okay, they're not exactly the same, but for the money you don't get a whole lot more. If you're deciding on 9800GT, it might be better to get something else.
I have. Yeah the extra futureproof things that come with it, seems silly not to. plus it claims it's a silent card.Reviews don't say otherwise too
Now the question of Q6600/E8400 LOL.