i5-2500k overclocking and offset voltage

[skulpturfungus]

I'm currently using a i5-2500k at 4.1GHz with my mainboard's (P67 Sabertooth) auto settings. Originally, I wanted to go up to 4.2, but that's where it starts getting temperatures up to the 70s and I don't really like that. I assumed that if I can get it to a lower voltage (it's at 1.296-1.304 on load) Thus, I tried to read up on manual overclocking and it's all fine and dandy, except for the vcore offset setting. Problem is, I don't really understand what value I should use. Can anyone help me out on how to determine that? Because everything that I've been reading up on so far has been inconclusive on how to determine the best value for that setting.

To add some info, currently, the CPU is running at 1.272V (fluctuated between 1.264-1.280 during a Prime95 torture test) and the VID is at 1.3711-1.3761 at load (again, fluctuated between 1.3661 and 1.3811 during a torture test).

 

[skulpturfungus]

I did some reading and I tried an offset value of -.075 while lowering the LLC to high and CPU current capability to 130%. Seems to run stable at the same vcore as it was before with manual under load, drops to .920 when idle.

Just wanted to ask if I did something horribly wrong before I keep it that way. Here are my settings before this post, so just assume that the values I've mentioned (LLC, current capability, manual->offset) here have been changed.