Multiple BSOD's with varying codes - all implicating ntoskrnl.exe

Hi Team
I've recently started getting various crashes & BSOD's whilst playing ARMA 3 (and on one occasion while running prime 95)
The errors have ranged from STATUS_ACCESS_VIOLATION 0xc0000005 errors which crashed me to the desktop to BSOD crashes with the following codes:-
0x0000001a
0x00000101
0x00000124
0x00000050

The constant thing linking all of the BSOD's is that ntoskrnl.exe is given as the driver or address causing the error (along with atikmdag.sys & hal.dll in a couple of cases)
As the collected wisdom of Professor Google points to causes as diverse as hardware failure, bad drivers & overheating I though I would ask here in the hope of getting sage & reliable wisdom!

I have read the pre posting guidelines & have attached the DM log collector findings & the information provided by Bluescreen View.
Hopefully my system specs will appear alongside this post but just in case:-
Custom built pc
ASUS P8Z77-M PRO (LGA1155)
Intel Core i5 3570K @ 3.40GHz
GSKILL Ripjaws f3 12800 ddr3 8GB RAM
AMD Radeon HD 7800 2GB
OCZ 80GB solid state system disk
2 x 930GB Hitachi HDD in RAID 0 config for data

Oops my bad - it was late at night though!
unfortunately the html doc created by bluescreen view would not attach