Is there anyway to know the memory temp of GPUs like rx580s and 1660super? Why is no one worrying about them? Is there any software that can show these cards memory temp? I've never seen anyone talking about this than the 3070ti ,3080 and 3090s, small cards don't have memory temp issues?
If the video card manufacturer has not installed a temperature sensor, then it is not needed there.
You can install it yourself, but it will be an additional waste of money and will result in a loss of warranty for you.
The 1660 and rx580 are not hot video cards, so I wouldn't think of unnecessary problems for myself. But you can change the stock thermal pads, this will reduce the memory temperature.