BSOD On Random Times with Random Bsod ntoskrnl.exe

[FireNose]

i just buy a decent gaming pc with the prices about 600 $

processor : fx-6300 six core
graphics card : gtx geforce 650 ti
ram : 8 gb
anti virus : eset nod antivirus 32

i buy the pc without hardisk,since i want to use my old hardisk.
since the first day i buy the game a bsod apeared,but cuz i have little time
i never go to the shop again.until i think after about 5 month the pc can't
boot and always stuck on the startup with black screen and no cursor.
before that happend the pc always got bsod or sometime just a blank screen with random color,the bsod is always random,sometimes it say bad_pool_header or irql_not_less_or_equal or something like that.so i bring the pc to the shop,it say that my hardisk and graphic cards is broken,so i change the gpu to nvidia geforce gt 740 and buy a new hardisk.

and so i re install windows and buy a new casing,the bsod appear again with bad_pool_header.i was desparate since am not computer expert so i don't know what else to do and the shop where i buy is just a dead end since they don't really know what's wrong.so i browse the internet,run memtest,downloading the blue screen viewer,and i suprise that i got so many bsod with the same driver error,ntoskrnl.exe . so i browse the internet searching how to fix ntoskrnl.exe bsod. but i don't have time to do all of the method.

oh and all the bsod i got according from bsod viewer :
bad_pool_header
irql_not_less_or_equal
Memory_Managment
Page_Fault_in_Nonpaged_Area
KMODE_EXCEPTION_NOT_HANDLED
BAD_POOL_CALLER
SYSTEM_SERVICE_EXCEPTION
NTFS_FILE_SYSTEM
DRIVER_CORRUPTED_EXPOOL
REFERENCE_BY_POINTER

and looks like i have about 50 minidumps file

sorry for bad english and word.
right now am desperate and i think my computer is malfunction

 

[FireNose]

got another bsod when playing gta 4 with a meassage bad_pool_header