Alright so Shikhar, sorry for not responding for a while, but how about these specs? xD I'm still looking for a computer and will keep searching until I find one for around 300-400 that will be able to run games like Arma 2 without a horrible lag, I don't mind terribly about the graphics, but I don't want any lag.
Model Predator G AG3620-UR318
Type PC Desktop
Processor Intel Core i7 (3.4 GHz)
Hard Drive Capacity 2 TB
Hard Drive Rotation Speed 7200 RPM
Memory Type DDR3-SDRAM
Memory (RAM) 12 GB
CD / DVD
Optical Drive Type DVD-RAM/±R/±RW
Graphic Card NVIDIA GeForce GT 630
GT 630 is crap...
Instead get an i5 as suggested by 13thmonkey probably a 3570 or 3770 (you can get the k versions if ur going to overclock) and 12 GB ram is overkill, 8 GB will be more than enough and invest the remaing money in ur GPU