Theres alot of different questions been asked here, and I get the impression your not fully aware of what your doing OP.
LLC is load line calibration, there are different levels for this, each level changes how your cpu voltage works. When you set your cpu voltage in bios, once your in windows it will show roughly what you ste in bios. However once you put the cpu under stress or load, the voltage will drop this is supposed to happen and its called vdroop. The different LLC levels determine how much the voltage changes. Generally the most used level is Ultra High.
When you stress test, use prime95 and use the torture test, then change ram amount to use 90% of your available ram. If you encounter BSOD 101, that means you need more cpu voltage. BSOD 124 can mean need more cpu voltage, but can be related to unstable memory, incorrect bios settings, CPU PLL voltage too high or low etc etc the list goes on. Best to cross that bridge when we get to it. If one worker fails, this can be indication you are near stable, but need slightly more cpu voltage.
If i were you OP, I would have a look at this thread I made here which helps people to overclock 2500k/2600k - http://www.overclock.net/t/1100100/info-intel-2500k-2600k-overclocking-tips
Its not the be all end of guide to overclocking, but look at the thread and you'll see alot of people have used that guide and got thier overclocks good and stable.