So would this be a good program to test stability for an OC?. As I was using OCCT and ADIA64 for stress testing both passed on my OC but then I did my first video encoding and the system BSOD!?. So not very confident on those 2 program's to give a good indication if your OC is stable or not
For stability testing (and general "finding the right OC settings") I'd recommend starting with Intel's Extreme Tuning Utility (XTU), use the CPU stress test at 5 min there to test stability, and use the profiles to remember and modify your settings after each stable test. Once you've found the right settings, go for a ~10 min AIDA64 stability test. If that crashes, nudge the voltage up a little and try again until AIDA64 is stable too. Then try Handbrake ... if that manages to encode a feature length film I don't think you'll see any other crashes. Once you've got all the settings stable through XTU, write them down and enter them in the bios.
This is what I did anyway and it has worked well ... not seen any crashes since sorting my overclock this way.