8x Gigabyte 1080s

So I got my gigabyte 1080s but I'm not sure how to OC them, as I thought my AMD experience is nothing in nvidia so any help would me much appreciated.
I'm using EWBF miner 0.3.3 version and I got around 425h/s on each card (while 0.3.4 version gives around 150h/s, why this could be happening?), also driver version is 378.78. I'm confused caus every time I try to OC hashrate drops, any ideas?

Are you using Windows? My next question would be, why are you using outdated drivers? Any special reason?

I'm using windows 10 64x and I don't know why I was using older version, I will update them asap

try this:
force solver 0 (in your .bat)
OC +100
MEM +500
TDP 85%

OC +185
MEM +600
temps are bit high but another air conditioner is on it’s way

Thinking to get 16x evga 1050Ti FTW, I think this are bets option atm but didn’t found anywhere their hashrate on equihash on eth they are like 13-13,5, but mining with nvidia on eth? noo