first time overclocking help. i5 2500k

so i've had my computer for a few years and haven't really touched overclocking (beyond what my board offers as standard, but it was unstable). but with the release of witcher 3 i figured i'd see if i could overclock my cpu so i could play. someone suggested i just use the ASUS AI suit tool on my pc (the turboV EVO tool) but the suggested specs weren't stable (crashed when i ran heaven benchmark and prime95).

wondering if i could get some help/suggestions on where to go from here, like i said this is the first time i've even attempted to overclock. i don't really see much point going beyond 4.0Ghz so i'm hoping it won't be too complicated.

specs
CPU: intel ik 2500k
heat sink: arctic cooling freezer 7 pro
motherboard: ASUS p8p67-m Pro rev 3
RAM: 8GB (2 chips) corsair xms3 12800 DDR3 1600Mhz
GPU: evga gtx 770
PSU: 650 watt corsair CMPSU-650TX
case: coolermaster HAF 922

http://www.overclockers.com/forums/...Beginners-How-to-set-your-25-6-700K-to-4-5Ghz this should do you well.

so i tried that with turbo set for 3.8Ghz and ended up with a (what i would assume) high core voltage of 1.32 according to HWmonitor and cpu-z. other posts i've seen report around a 4.0Ghz overclock for the same cpu only needing about 1.2 to 1.25v.

i'm not really sure what setting i'm missing in the bios that would change this.

so i found out there isn't a direct way to change core voltage, but i was able to set a - offset for the turbo voltage of .1v. now my cpu core voltage at idle is about .85v and with prime95 it maxes out at 1.24v (though it mostly sat at around 1.2v). not too sure about stability yet but it didn't crash in the 20 minutes i ran prime95 so i'll start a game later and see what happens.

my only worry right now is the cpu temps get pretty high, at least according to HWMonitor. it reported that the core 0 - 3 temps hit 80*c along with the package before i stopped running prime95. is this an issue, or does prime95 just superheat the cpu (i'd guess it would, but i figured i'd ask).