I did memtest on both sticks of ram together and individually, and in the three tests, for 9 passes there were no errors, so it seems its not a RAM problem ryt?
no , because any memory testing program doesn't stress ram like windows the only true way is to run in a windows environment, to quote since windows 95 Microsoft have stated about memory testing programs
Defective memory chips may not be detected by memory checking tools. Some memory checking programs are not adequate tests because they do not test RAM in the same way that Windows uses RAM. Most memory checkers use read/write cycles when scanning memory. Since Windows is executing code from memory, it uses execute cycles. Execute cycles are different from read/write cycles and are more vulnerable to parity errors. It is possible for memory checking programs to find parity errors if the memory is extremely faulty.
take out all but one stick of ram and run your system for a few days trying your best to make your system bluescreen

let us know it goes
My Computer
- Computer Manufacturer/Model Number
- built my own
- OS
- win7 ultimate / virtual box
- CPU
- Intel Core i7 3770K,1155, Ivy Bridge
- Motherboard
- MSI Z77A-G43
- Memory
- GSkill Ripjaws Z Series 1600 CL 9.0 16GB
- Graphics Card(s)
- KFA2 GeForce GTX 670 EX OC 2048MB GDDR5 PCI-E gfx card
- Sound Card
- onboard Nvidia HDMI audio
- Monitor(s) Displays
- ASUS VK222H 22" widescreen LCD monitor
- Screen Resolution
- 1680x1050
- Hard Drives
- Kingston 128gb SSD
OCZ Vertex 90gb SSD
500GB WDCaviar 16mb 5000KS
320GB WDCaviar 16mb 3200AAKS sata 2
1TB Samsung 16mb HD103SJ sata 2
- PSU
- Corsair HX 750W ATX2.2 Modular
- Cooling
- Antec 25 Kuhler H2O 620
- Keyboard
- logitech
- Mouse
- logitech MX518
- Internet Speed
- 7mb adsl