Budget PC for 10k::AMD::????

My dad is gifting my cousin a PC on his B'day he is in 8th standard. I thought I can help my dad.
So we are talking about a 14 yr old boy he loves to play games like nfs COD CS and more. I thought of getting an amd as they are cheaper than intel. I have never got an amd before so no idea.These are the configs. in my mind need ur suggestion.So pllzz help.
AMD processor(equivalent to e2140) plz provide me with the model no.
Motherboard(????)
1gb ram at 667 mhz(kingston)
xfx 8400gs
Sony dvd-rw
80gb HDD
Generic cabinet with cheap 400w PSU
The monitor and the speakers are not required so what i want to know here is the proccy and the mobo with there price

refer this thread...might suit u

Need Help: Choosing a CPU / Mobo

The sempron LE 1100+ with a nforce 6100 motherboard can be bought for under 4K. the sempron is a single core processor which runs at 1.9 ghz but it is enough for games like COD and CS. Infact I used to play CS: S on a ati 9600 pro and amd2000+. ( used to get 40-50 fps on low settings).
The Gigabyte GA-M61SME-S2 is a good motherboard which can be bought for around Rs2300.