Does someone have working OC for this card?

So I utilized my gaming rig to mine, which has a Gigabyte RTX 2070 Super Gaming OC. Not a great card, I know. After fiddling with Afterburner for 2 days, I still can't find any meaningful change without NBMiner bringing reject shares on the table.

Now I'm running the card with a Core offset of +80 and power target at 68%, which gives me a hashrate of 20,8-21,70 app. No offset on memory clock.

Anyone has a better setting for me please?