Can't get past 3.8Ghz

Just as the topic says, i can't get past 3.8Ghz on my 4670k without the fans going 100% on H75, any reason for this? (Asrock z87 Extreme6 motherboard and around 35- 40c, still 100% fan speed)

Did you set your fan speeds in UEFI? Set them to custom and specify what speed/temps you want your fans to run at.

Also, make sure those temps are correct. I like realtemp, or AIDA64.

I agree with phantom on the temp plugin I use coretemp. They are essential to ocers you can set alerts and it runs in your taskbar  for easy viewing. Another thing is overclocking is not always sequential. What I mean is for instance my 3820 overclocks from stock to 4.0 it will not overclock from 4.1-4.3 and is stable at 4.625 and 4.8. You may want to try jumping around on the freq spectrum and not just increase or decrease slightly once a wall is hit sometimes 400 mhz can get you back into a stable freq. I usually have 3 OC setting in memory and they are 200+/- apart from each other ie  4.4 4.6 4.8. I only use 4.8 for benchmarking since 4.625 is not much worse and the temps are substantially better. Also thermal paste and possible air could be worth troubleshooting as well as the fan curve gradient.