I had a nvidia geforce FX 5200 in my computer and when i played games it didn't have the performance i need so i figured out what kind of slot i have and watts for my computer(450W) and i bought one at tigerdirect.ca and thats the ATI radeon x1650 Pro AGP

More info:http://www.tigerdirect.ca/applications/SearchTools/item-details.asp?EdpNo=3101648&CatId=318

so i bought it i did research and i was confident it was going to work so i opened it up and did the proper installing it into my computer but for some reason the my monitor(dell 2001fp) trying DVI-D and VGA and it wouldn't work and just stayed in power save mode so now i have to wait for my cousin to come visit and try to fix it (he is a computer guy) but i have no patients because my summer is almost over 1 month to go doesn't anyone know the problem please help

Check the refresh rate, as well as the default resolution for that card against the supported modes for that monitor. If the card has a default setup that is not compatible with the monitor, then it will not wok. Check, and repost.