@sankarshan, are you talking about 4000 INR (~ USD$60) ? Is my assumption that you're located in India correct?
Addendum: If so, then it looks like you could get either a new Nvidia Geforce GT 730 or Radeon HD 5450. Personally, I would try to get a better card by purchasing used.
yes i am talking about 4000 INR ,i am located in india,also what is the firstmost criteria i should consider for purchasing graphics card if i manage to take some other graphics card???
@sankarshan, in answer to your question "What is the first-most criteria i should consider for purchasing graphics card?", I would simply respond that you're generally trying to get the most powerful graphics card in your price range. If you'd like a general idea of hierarchy of graphics cards, then this is good resource:
The least powerful cards are on the bottom and they get progressively more powerful, as you work your way up on the list. The left column contains Nvidia cards and the right AMD. Ideally, it would be great if you could get a GTX 750 or 750 Ti (Titanium) but those are at least twice your budget, if not more. Also, your AMD sempron will most likely be a bottleneck regardless. I don't say that to be offensive but instead to be complete transparent in my thinking in reference to your computer build.
Addendum:
I actually used to have a very similar computer. I previously had a AMD Athlon 3500+ but mine was a single core CPU. I'm reasonably sure that your motherboard only has a first generation PCIe Express 16x slot; current computers have PCIe version 3.0. If my assumption is correct then your computer will only support a graphics card with only one generation newer than yours, PCIe 2.0. Anyone else reading this message thread, please feel free to correct what I'm stating as I'm not 100% on this point. I don't think this is going to be much of a problem, because the low budget will probably only allow buying a card of that generation anyway.
I have Radeon 5450 ddr3 2gb graphics card and two 2 gb ram cards in my pc
Can i get a list of few latest games that will work on it ???
Pc specs-windows 7 ultimate,64 ,amd semsempron,145 processors,2.8 ghz
Sorry, but pretty much no recent games wil run at all on those specs. If you are wanting to run the latest games on decent settings then you will need more powerful specs.