Ubuntu is more graphical in nature than other linux distros. So it will consume more GPU power
~snip
No, actually Ubuntu uses the same amount of GPU power as other distributions if they run the same desktop environment. Bigger desktop environments will however use more GPU than smaller desktop environments (Gnome > KDE > XFCE...)
And besides, on Linux hardly anything uses the GPU except for a hardware-accelerated web browser so GPU temperature is not going to go much high.
Low end CPUs generally get high temperature quicker.
This is not correct, lower end CPUs have smaller clock speeds and more powerful CPUs have higher clock speeds and the higher the speed, the hotter the processor gets. It's basic thermodynamics.
CPUs have 3 or 4 built-in speed "levels" they switch between to adjust the clock rate, they don't run at arbitrary speeds in their range.
They also have a turbo mode that temporarily increases the clock speed to a higher limit until the processor gets very hot. This is what happens if you see 100% CPU usage.
Take note that all of the browsers do take a high capacity on a user's RAM and running an auto-bet in a browser would simply make the browser run more as the user would open more applications other than that.
More RAM usage does not increase processing therefore cannot make a computer heat up.