I see thins topic discussed over and over but with no end result or conclusion. I understand enabled over volts the CPU and disabled undervolts it. also enabled protects the CPU from spikes. the question is weather or not vdroop is a good thing or a bad thing? How does it work exactly?
 
Example:
my cpu is overclocked at 4ghz / no turbo / with HT at 1.2v in bios. in windows at idle it shows 1.2 - ok but under load it shows 1.18v. does this mean if i set 1.18v in bios it will still be stable under load?
 
is this how the true voltage under load is found with vdroop on?
 
the reason im leaning more toward vdroop enabled is that it just seems to be better for temps and the cpu. please corect me if im wrong and advise any input on this matter that seems to not have an answer.
 
Thanks guys

Your pretty close.
Having vdroop enabled, means your voltage will drop under load of course. Once you are stable you can view the vcore under load like LinX and see what the voltage is that it drop down to. Ideally for overclocking you want to find the sweet spot, which is just above where it failed previously, so you know you are not giving it more vcore than really is needed to remain stable.

Ok so you have vdroop enabled at 1.2 vcore in the bios, and it drops down to 1.18 under heavy load and remains stable.
If you disable vdroop, then what you set in the bios will be the min voltage, ( with the exception of say speedstep/cxe being enabled) and as load is added to the system, your vcore will actually increase.  Mine typically increases in the neighborhood of  around .02-.03v.
So technically, you could probably get away with setting an even lower vcore in your bios, to where it hits around 1.2v whilst under a heavy load like running LinX or Prime.

What this gets is lower vcore at idle, hence lower cpu temps when the system is not under load. Some fear that a voltage spike under heavy load may hurt the cpu, and is why vdroop is there in the first place. Certainly it was designed as a safeguard, however I have been on these forums since 2007 and have yet to see anyone at least on these forums have a problem with this.

It really boils down to a matter of personal preference, some like not having vdroop, others prefer having vdroop. Back in the 680i and 780i days, many overclockers would use the pencil trick to shade between the appropriate transistors to achieve the same - with the X58, we now have it as a bios option.

I myself prefer to disable vdroop and have the lower vcore setting at the start.