Newb. Learning with Nicehash/CCminer. CCminer crashing intermittently

[nuvominer]

Hello. I am currently learning how to optimize my gaming rig (1x GTX 1070 G1 Gaming, slight OC) for mining before investing in a 6 GPU setup. I have CCminer mining Zcash @ ~280 Mh/s. It goes fine for 20-30 minutes before crashing and auto-restarting. Curious if this is due to my GPU settings? Here is my settings http://imgur.com/a/jrQI9

Also, how much work am I losing when the miner crashes. I read elsewhere only the last few SOLs, but would like to confirm this. Thanks for any help.
 

[miliard]

Im not familiar with that GPU but it could actually be too much OC w/o adding voltage/power limit. Try it on stock settings and you will know for sure.