Assembled PC is always come into the picture when it comes to performance. but only and only when you have chosen good hardware as per with good prices.Like if you want a ideal computer for gaming then what will you prefer a 1lakh pc or a pc by asus or alienware? I think you are wise enough to choose choose the first one, behold you could have chosen a bad components for your PC!
but dont worry there may be I can fix this. this is the great disadvantage of a assembled PC selection of good and adaptive component. let me tell you how to select the ideal components for your PC-
*hard disk** - for hard disk I would suggest kingston or seagate hard disks. because they are efficient and cheap. will cost you 3000
*motherboard** - choose any motherboard in ASUS and MSI range of series. they are always the best and not so costly.(asus Z and A series is worth buy) cost- 6000-14000.
*RAM** - go for min 4GB RAM with DDR3 as if support for perticular motherboard(ddr may vary as per specification of motherboard).#must check motherboard specification before buying a RAM. cost- 2000-3000.
*Graphic Card** - If have a gaming love like me. then the ATI READON 5770 1GB will the best buy for you. I think this is the best and value for money graphic card in the market till now. cost- 6000Rs
*power supply** - it is not focused but very precious part of PC. Dont buy any cheap power supply for consumption. check the pins i.e 20 or 24 pins as per requirement. and in the output 200 to 1800 watt and 15 amp outlet is ideal for any power supply. system performance is mostly depends upon the coolness of pc. and that can be maintained by power supply only.
Congatulations for your ideal pc. enjoy its all your day:)