if the problem is still occurring, it's probably your IMC that can not handle it (or might need a little bump in voltage). 4 sticks of RAM that are rated as low as 1600MHz can stress your CPU's integrated memory controller pretty hard depending on the frequency which is one reason you may have had no problems overclock with 2 sticks but, immediately BSOD with 4 sticks.
if it's the 1600MHz rated corsair vengeance, id recommend sticking to the default XMP profile.
im assuming you raised the frequency to overclock the ram but, how much? 1866MHz? 2133MHz?
- have you touched timings at all? (loosening timings may help you achieve a stable overclock but, with 4 sticks it's hard to say).