Vega 56 ref(samsung) with 64bios - L24+24 best - 19500hr 1230/870mv-gpu and 1100/870mv mem - 120/127W in GPU-Z(temp=57° fan=3000pm)
this card go more up but my power is to low for 1400gpu
Vega 56 ref(samsung) with 64bios - L28+28 - 19250hr 1230/866mv-gpu and 1100/668mv mem - 112/122W in GPU-Z(temp=57° fan=2700pm)
You should be able to lower your core clocks even further to 850 or even 825. Also, max your mem clocks to 1107. That's as far as you can go on equivalent SoC.
I've noticed that accessing Teamviewer will crash my rig when running low clocks and high intensities. Also, I'm now using a staggered approach: I set higher clocks and voltages, start the miner, and once all cards are up and hashing, apply lower clocks. Just a little script with overdriventool on a timer. Works wonders.