i haven't had any problems with the 2x sapphire x1950pros i have in my lanparty rig, they are great, can sometimes even out perform an 8800gts320! they were cheap too, i say since you have a PCI slot cooler you should be fine if you get that sapphire one, even though i personally have had no trouble with them.
I have the ASUS one and it runs extremely cool. I went from an x850xtpe that was nicely overclocked to this card and the difference was definitely not worth the money really, but it is a good card. Mine is running at 640/1410 right now which is a decent overclock and the temps are great. I HIGHLY recommend the asus version though. Even with the fan at 100%, my AC Freezer64 is louder (and it is very quiet).
I plan to add a second for crossfire real soon because I found one for cheap.
Just stating what I know based on my own experience. I got a 1950Pro to replace a 6800GT. In most games I've tried, FPSs single-player RPGs etc it improved my frames and in turn allowed me to play with a little bit more effects turned on. Nothing mind-blowing as I expected but good nonetheless. Now there are a few games, Pixar's Cars ( Son plays 5yr old) and World of Warcraft which either play with some glitching/crashing that was never present before the upgrade and have found no other cause and also they run at about 10FPS SLOWER than my old 6800GT. The unfortunate part of the story is that as much as I love FPSs and other games my PC plays WoW and Cars more than anything else and I get decreased performance for the $250 (at the time) that I spent.
Oh well, depending on what you play I might recommend the card. If you are a WoW addict you might want to stick to Nvidia GPUs from what I've seen firsthand.
In regards to all the posters mentioning other 1950pro models, I was trying to keep the additional money out of pocket to a minimum. It sounds like it needs more power than my PSU has.
How about the 7900gs? I recall reading that it overclocks well, putting it to about 1950pro levels?
The 1950PRO uses 65 Watts of power, or about 5.4 Amps from the 12 Volt Rails. You could probably run it on a 350W PSU with 20A on the 12V rails. Of course it depends on your other system components too.