Need advice for Video card replacement

Would like to get an upgrade for my video card. What is the Max I can use for a card and what would be a good choice? Like to keep cost to $120 mark or less. I play World of Warcraft. At some point I would like to attach to a TV.
DELL Dimension 8400
Intel(R) Pentium(R) 4 CPU 3.40GHz
072 Mb Mem
NVIDIA GeForce 6800 256 Mb PCI

He said he has a 6800 PCI, I don't believe I've seen any 9600GT/4670's on PCI.
However a quick google reveals that the 8400 has a PCI-e slot.
A 4650/9600GSO should be able to max out WoW at medium rez (correct me if I'm wrong). I'm pretty sure any PSU that Dell uses for a P4 can handle a 4650.

I can anwser PCI-e X16 for sure. Have to check on the motherboard. Got the system about 4 years ago. I know I will need to upgrade in a year or two. I can change the power suply if needed. So im going to guess that I'll need to do a lot more if i'm ever going to get WOW in full detail?

GF9600GT actually uses much more power.

If your options are PSU limited, then the HD4670 and even HD4770 would require less power than the F9600GT, but the HD4770 would be wasted on something like a P4, and you're paying a premium for it.

And while you could get something now and then use it in your upgraded rig later, I would recommend instead of wasting money on and HD4770 or HD5750 now which are still a little pricey IMO, I would get the HD4670 now and then take the savings and upgrade later to something better as a whole system upgrade once you've tried the HD4670 in the new rig.

What resolution do you play at? For a p4 with an unknown PSU a 4670 is probably your best choice.
http://www.newegg.com/Product/Prod [...] -_-Product
That assumes however that you have a PCI-E slot on your motherboard. Can you check to make sure you have a PCI-E slot and check your PSU wattage while you are in there, if its a good one you might be able to use a 4850.

Thank you everyone for the responses. I figured that my system is limited by both the power supply and more important the chip set. I guess I just needed it confirmed. Drats! I will do some reading on the HD4670, it sounds like the way to go. I’m sure I will see an improvement in my fps. I just wanted to make sure that I did not waste my money on something that my current system can’t use fully. . Much as I hate to admit it I’m going to half to dig deep and start saving to build my new rig if I want WOW to really wow me.