Why is there an inverse relationship between voltage and temperature?

Question

Processors

Hi all!
I'm testing 2 new absolutely identical laptops with a 9750H processor. I'm trying to do undervolting. Please help interpret the results.
So, there are 2 identical laptops:
1) Maximum undervolting -180V .
In a stress test, it keeps a frequency of 4 GHz at a temperature of 80 * .
2) Maximum undervolting -160V .
In a stress test, it keeps a frequency of 4 GHz at a temperature of 70 * .
Why is there an inverse relationship between voltage and temperature? The lower the voltage, the higher the temperature. How is that in general? :)