GTX 980 overclock question

[th3dud3]

so i am kinda new to the whole overclocking thing and i could use a little feedback.

 

right now i am running two MSI gtx 980 ocv1 in sli, both watercooled. Using MSI afterburner i have been able to get a max stable overclock of 259 core giving 1550 boost core clock, and 500 memory giving 4000 memory clock . From what i have seen around the web this is a pretty decent overclock for these cards.

 

my question is this:

i haven't had to increase the core voltage at to acheive this overclock. up until today i have had the power limit @ 125% in msi afterburner, but today i enabled power usage monitoring and i noticed that, at least while running valley and the witcher 3, that the power % reported by msi afterburner never really raises over 100%.

 

just to see what would happen i decided to lower the power limit and i have noticed though that if i lower the power limit to 105% or 110% that i get random crashes. these crashes occur even though afterburner reports the power usage in the mid 80% range. i haven't done any thorough testing to find out what power limit i need to keep this stable, i simply lowered it to these levels to see if there was an effect on stability.

 

i am just wondering why afterburner is reporting such low power usage. is this normal, are other people seeing this?

 

Is there some fault with afterburner?

 

is there an issue with the statistic reporting from the cards? (it should be mentioned that i am running newest nvidia drivers, and have newest MSI bios on the cards)