So about 6 months ago when trying to manually set the voltage for base speed on my 4790K I accidentally typed 1.800v into the CPU rebooted and then loaded into windows and realised so immediately rebooted and set voltage back to normal.
Another member said i wouldn't have done the CPU any long term harm coz I didn't stress test and temps were normal range on boot up.
Also asked a local PC tech who confirmed it shouldn't have done any damage as I didn't run anything heavy.
PC has been running fine ever since.
i7 4790K @ 4.4GHZ 1.145v/Asus Maximus VII Ranger/16 GB Kingston Hyper X Savage Red DDR3-1600MHZ 1.5V/Asus ROG Strix 1080ti OC 11GB/EVGA 750W Supernova G2/Corsair H110i AIO Cooler/Corsair Graphite 780T case