If you are in search of a gaming computer within Rs 45000 then you are in the right place. If you are a professional gamer then you may ignore this post and for you specially another post is coming up. If money is not a factor then I must suggest you to go for alienware desktops. They are the best in the market. I do not prefer alienware laptops as they are bulky and moreover gaming is considered to be less locomotory so desktop is much better than a laptop. If you want to buy alienware desktop you can check this link.
If money is a factor and you want to squeeze the value out of every penny then you may choose to assemble your desktop. Its not rocket science. Its very easy and self doable. If you need help regarding that, feel free to ask in comments, I shall help you with that.
For the aforesaid budget the best computer configuration which you can build is an Intel i3 processor based PC. Many, in fact most of the gamers, prefer an AMD based PC and I can not deny that at the same cost you will get a more powerful processor from AMD but if you are looking for hassle free PC experience then go for Intel processor based PC. Or if you are from Greenland, Siberia, Canada, Kashmir where the temperature is always below 10-15 degree Celsius then AMD processor will help you (pun totally intended). I am from India and I have a terrible experience with the fastest processor in the world (of 2012) which is an AMD. It used to average at 60 degree Celsius and on load reach upto 80-90 degree Celsius. My room is the coldest one in my house but I never required a heater in my room during winters. Thanks to the processor. Now don’t ask me about my experience during summers. 😛

Its your computer so decision is yours. Here is the computer configuration which you are seeking.

Gaming computer within Rs 45000

Processor : Intel i3 3220 at 3.3 Ghz – Rs 7100
Motherboard :  Asus H61 M-C at Rs 3700
Graphics card :  Asus NVIDIA GTX650-E-1GD5 1 GB GDDR5 at Rs 9000
PSU : Corsair 450 Watt at Rs 2750
Monitor : Dell 21.5 inch full HD monitor at Rs 8850
RAM : Corsair Vengence 4GB at Rs 2900
HDD : Seagate Barracuda 1 TB at Rs 3900
Cabinet : Cooler Master Elite 311 at Rs 2650
Speakers : F&D f203G at Rs  990
Mouse + Keyboard : Dell USB Keyboard Mouse Combo KB212 MS111 at Rs 560
UPS : I highly recommend using a UPS. APC 600VA will be around Rs 2200. Its very good.

The total cost of this assembled PC is Rs 44600 You may chose to give a small treat to your friends with the remaining Rs 400 or you may buy me an item from my Wishlist.  🙂

If you have any queries, feel free to ask in comments. I shall be glad to help you.