If you want only for gaming, keep in mind that today a 7600GT + AMD 64 single core > Any dual core + 7600GS, just keep in mind that the GPU is the ONLY thing that counts. CPU matters, but not as much. And most CPUs today play most games fine with good graphic cards.
Extend your budget as 38k is just too low.
GPU: Geforce 7900GT : 17k+
Geforce 7600GT :>10k
RAM: 2 X 1GB DDR 400 or DDR2 533/667
Both of these are constants as :
if you buy a difference card, it would still cost atleast as much.
anything lower price isn't recommended.
2gb RAM is required to use the system even with this card, else games would be crap. less than DDR2 533 may be too slow, so not recommended again.
HDD: 160GB SATA II NCQ : around 3k or so, not sure
FDD+DVD RW+COMBO=4k
Generic cabinet + Powersafe 450-500watts, or cooler master 430: around 2-2.5k
again, all things till now are constants
Monitor: Samsung 798MB Plus, 6k or more
Mouse: Microsoft Comfort 3000 : 800+
Microsoft internet/multimedia keyboard : >400
altec lansing 2.1 : 1500
Whatever is left is for the CPU+MB.
Case 1 s939
AMD 64 3200 + Asus A8N E + DDR 400 + aftermarket CPU cooling, you will probably be able to overclock it to 2.5-2.6 or more and then for the majority of games, there should be no problems. The entire bundle will be around 20-21k
Case 2
AMD X2 3800 + Asus A8N E + DDR 400
This will be fine for todays games and even better once overclocked, some games might not run that well especially without overclocking for some.
This bundle will be >23k,
Else you could replace the s939 cpu with AM2 and get a suitable motherboard without onboard video and one which overclocks well, is stable and a decent performer, and get ddr2 533 or even 667 RAM with it.
Don't exactly know the price of this one but should probably be around 23-27k.
Case 4
Intel E6300 + DDR2 (preferably 667) + MSI Neo F 965
This will cost you 25k
This may be the best combo. But you might need to get 4 X 512 RAM modules instead.
But you wouldn't be able to get this in the budget as the GPU costs around 18k, or atleast 10k+, so extend your budget to atleast 45-50k
