Where in India do you live?
Here's the configuration I suggest:
(Prices exclusive of shipping. Prices taken from online websites in India are indicative only.)
> Processor: AMD Athlon II X3 440 -- Rs.3,250/-
(You can unlock it to a quad-core with the motherboard.)
> Motherboard: Asus M4A78LT-M LE -- Rs.2,600/-
(No Crossfire.)
> RAM: G.Skill Ripjaws / Corsair 2GB @ 1333MHz -- Rs.1,100/-
> Video Card: MSI R5770 Hawk (with 2 fans) -- Rs.8,000/-
> HDD: Seagate 500GB SATA II @ 7200RPM -- Rs.1,800/-
> ODD: LG DVD-RW -- Rs.850/-
> PSU / SMPS: Corsair CX400W -- 2,600/-
> Cabinet: Cooler Master Elite 310 -- Rs.1,500/-
(It can support ~3 fans with 1 included. Consider buying the others later when you can afford it.)
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TOTAL: Rs.21,700/- ± 2% (shipping extra)
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You can use
TheITWares,
TheITDepot,
Primeabgb and
SMC International, if you want to order online. Compare the prices to see which one is the most inexpensive. If you live in / near Delhi, Nehru Place would have the cheapest rates.