Hashrate drop when using a 2nd GPU

[Breckel02]

I have been mining with an RTX 3070 for a while now and decided to add a 1060 6gb to my PC to increase my mining efficiency. However, after I plugged it in both cards are really underperforming. I should have enough wattage easily (EVGA 750W gold) to run both however they're both just dying on me and giving me less combined than I was earning alone with my 3070. Both have their own individual power cable going to the GPU. Any ideas what is happening? plz help I beg. Very new to mining

[MiroslauF]

Last days there was significant increase of Difficulty causes more than 30% lower earnings. I started with one GPU and adding GPUs (4 at this moment) always causes increase Hashrate...

[Rhacknar]

generally you don't want to use diffrent gpus if you had another 3070 this would be better option. also check your power maybe your power supply isn't big enough? a drop in your power usage below what is required to run both cards could cause performance issues. and the fact that they are 2 diffrent cards with 2 diffrent drivers could cause the miner to try and run them both and cause an issue.