That's the article I was just talking about! One of the posters had to run a wire to a regulator to boost the current to the card because the slot wasn't properly powering the card (hence why I ask about checking the power input on the card, and if the card supported reporting that info).
Here's the post specifically: https://forum.openwrt.org/t/mt7915-pcie-cards-on-bpi-unielec-boards/118194/14?u=netracerx