Should i get the ati 4870 video card?

I have a ati x1650 512mb pro pci-e, 2gigs rams, amd dual-core 2.2 with no vista. How big of an improvement would it be for the newer games. If I got the ati 4870 with 512mb. Is it worth to upgrade?

only if ati fight back soon the Driver of 180 made ati in deep depression
http://www.fudzilla.com/index.php?option=com_content&task=view&id=10559&Itemid=40
iv never seen in my life ati so low against nvidia does of a simple driver when at start of few month ago the review showed far better perfomrnace for 4870 now i'm sadi just want to cry when i see i fell like it what i got if i play dead space on pc.. a 4870x2 but it not in the shown :so i may get like 220fps-250fps and two 260gTx like 340fps.  huge failure but  ati did promise tehy would put the 4870 series back to the track they mean 4870x2 too right ?!
http://www.fudzilla.com/index.php?option=com_content&task=view&id=10560&Itemid=1
i would normaly say yes since of old review but just look at it. it make me sad (ati that is red is being beated up by just a driver update shame)

An overclocked GTX 260 can reach to GTX 280's performance. Same can't be said about 4870 because overclocking it barelyt juice up any significant frames.