Suggestion For A Good Graphic card Of Nvidia Or ATI

Hello Guys,
I want A good Graphic Card For my Pc but my system is very old [made=2003],i hav 512mb ram & Pentium 4 CPU with 2.28GHz.. My CPU Supports PCI bus 0,device 2 location graphic card...i hav intel 82845g graphic card which is too bad [in simple words it cannot run any game made in 2009 or latest]so i want to change it...please suggest me a good graphic card that can run with my pc requirements..& 1 more question that..Can we Run a ddr2 or ddr3 graphic card on DDR1 Memory RAM? please answer this one..i m too confused in dis..
thnks in advance.

this says tht there is no relation b/w ram & graphic card?totally confused.

Hey its true that there is no relation between the graphics card and the Ram. the DDR1 and DDR2 Ram slot will not be considered while choosing the graphics card. It is the motherboard that tops the criteria for choosing the graphics card. Since you have P4 then I guess that Nvidia card will certainly work on the motherboard. You can also go for ASUS if you are looking for something in gaming. I think that both of these card are very popular in the current market and you should also go for any one of them.