If he's switching an 9800 to an 1600, I don't think a 1950 is in his budget
Me, I'm in a similar situation, stuck with agp for now; will upgrade to C2D sometime
next year. Just look at the vga charts here and elsewhere and you'll see that
1600 < 6600GT < 7600GS < 7600GT < 800GTO is the usual order.
I'm thinking of a 7600GS, and from those, Galaxy makes very good ones (Zalman
cooling and higher-speed GDDR3 memory upgrades ). However, depending
on where you live, an x800 might not be much more.
These would be a difference you'd see. The 1600 is crippled imo, and therefore
weak, so not worth buying.
As you can see, the x1600xt is more in the 6600GT/6800XT category. It's strong suit are it's features & bundle mostly. In my opinion, it'd be a waste of money to upgrade from a 9800XT to a x1600XT.
There are some x1950Pro and 7900GS for under 200$ that will put this card to shame.
I think those cards are PCI xpress though. I need an AGP card thats better than the 9800XT. I am don't want to have to upgrade my motherboard to use the card. I checked around on Newegg and can't seem to find the AGP versions of the cards you suggested.
Both are significantly faster than your 9800XT, that will give you roughly 2x the fps you're getting currently. In the AGP segment, it's hard to find anything that gives you the same performance for that price (110-130$).
If you get one of these cards, you can last just long enough so that your next upgrade would be a midrange DX10 card, when those become affordable.
Keep in mind that neither of these cards are monsters, but they are both a significant upgrade from the 9800 and offer good value for their price.
Ideally I would look for an AGP version of x1950Pro, but I cant seem to find one for a good price, and 280$ is borderline pointless to pay for a card whose PCI-E version sells for less than 200$.
There are definitely better cards to be found for AGP, but they are grossly overpriced compared to their PCI-E counterparts. Almost to the point that you can get a new motherboard and PCI-E card for the price of the equivalent AGP version of the card.