problem unpacking games ?????

[sam002fc]

hello i have upgraded my pc
i have two 4gb ddr3 1333 mhz twinmos ram i3 2120 cpu @ 3.3 ghz , r9 270 gpu, 550 w thermaltake psu , ASUS p8h61mlx3 r2.0
my pc boots up normally i can surf web and can do normal stuff but whenever i try to play heavy pc games like bf4 , watch dogs , thief it crashes after 1 or 2 hour and when i try to decompress game files it give me checksum error or decompression failed message , when i try to unrar large files i get packed data checsum error everytime so i test those in my laptop with 4 gb ram i5 2450m cpu it ram absolutely fine
the details of my rams are
1. one stick is 8ic second has 16 ic
2.one stick is 256x8 mb stick other is 512x8 stick
but both ram is CL 9
so if i cnahnge my ram which one will i change 256 chp one or 512mb one
plz guys help this thing never occured earlier in my system and i am facing same errors individually when running each ram in single channel

 

[uplink-svk]

Those are great temperatures for stock cooler, but You might consider CM Hyper 212 Evo, or Gelid Tranquillo Rev. 2.0

 

[Alec Mowat]

yes stock is working great temp never gets 75 degree if i play watc dogs on ultra it sometimes get 78 degree but stays within 60 to 78 degree

78 it was too hot. Reseat the heatsink and get new thermal paste, make sure the case is well ventilated. 60 is optimal, I wouldn't go higher than 75 unless absolutely necessary for short periods of time.