I would strongly recommend against any card that is PCI or Radeon SE.
They are just not worth the money. A friend of mine has a Radeon 9200 SE, he bought it for £50 at the same time I bought my Geforce FX 5200. We have pretty similar set-ups, but his card can barely run many games.
They are both AGP8x cards, with 128MB RAM. It is the same as my other friend who has a Radeon 9600 SE, his card is only just faster than mine. Again on very similar set-ups.
Really I do not think alot of the Radeon budget cards. The mid-range though is something that interests me. The friends I have, either own the Budget (like me) or Performance Cards.
The Futuremark scores are confusing.
Scores I found for a system close to mine,
Athlon XP 1.8GHz 2600+, ranged for the 6600GT in Mark 05 from 2800..3500
To me this seems like a
huge speed difference.
I only found a single entry for X700 cards, which was 3005. Problem is it doesn't note if that is the XT/PRO/Standard cards.
It appears that the RAM in Mark 05 has alot to do with the speed.
So that makes the 6600GT around the 3000 mark for my system.
Wish there was a 6600 to compare this too.