That reading is showing the gpu core temp…not the vram memory temp…that could be overheating (being a laptop, probably even better odds) blow out the vents, and if you’re able, consider opening the laptop and replace the thermal paste on cpu and gpu.
Make sure in Nvidia control panel to NOT have Prefer Maximum performance selected…will only keep your gpu hot.
Also you’ll get less heat and better performance if you turn hyperthreading off imo.
I think you’re probably dealing with heat and my guess a 192bit memory bus in the gpu (nothing can be done for that)