GTX 1070 8 Gig Micron Mem 14 hashrate

Hello. New to mining.

Problem. All three cards are low hash rate. Tried various over clock with little success. I have attached photo of cards and their settings.!

Screenshot 2021-06-06 at 01-56-07 Slaves undefined n a - UserUnknown7007 farm|690x234

GPU0 Cards mines 25 hash
GPU1 Card mines 14.XX hash
GPU2 Cards mines 18.XX hash (that is a 6 gig)

My drivers: (current 455.45.01) I downgraded and got an extra hash on GPU0 card from 24-25. I was at 460.XX.XX driver before for all three cards.

Power is 850 Watt. Power SDD and 3 GPU, CPU

Not sure what else you need; the .img does show at bottom the hardware build
My real concern is this: My sons RTX 2060 gets 23.60 on Nicehash 60 watts and no overclock. its on lite setting. My cards are 2 x 8 gig and getting nasty hashrates, as well as, my 6 gig is getting better than one of my 8 gig cards.

Action taken to improve:
I have changed drivers from 460.XX.XX to (current 455.45.01)
Tried overclock values from 0-200 Core and 200-800Mem. To high just crashes but later I read its prob because I did not increase power. My power handling was 100watts and is now 115 wit the same hashrates as listed above.

Bios settings are simply GEN 2PCI , Enable 4g, CSM enable run legacy. graphic out are switchable such as internal or GPU card. I do not run monitor.

Honestly any help and suggestions is very much appreciated.
Thank you for your time.

Okay just for the sake of it I tried a NEG -200 MEM on GPU1 Card. Here is screen shot. My hash rate jumped from 14 to 20.86 hash rate

Can I get some suggestions on what is generally safe and why this -200 mem did the increase in hashing power? Also, do I have to turn miner off every time I make a overclock change? What is really happening when i make the -200 mem? Thank you very much. Any thoughts on what I should be clocking too? My fear is running to much power and not making return.