Upgrade Lenovo YOGA 3 Pro Processor?

Very few current laptops have a way to upgrade processors, and that has been pretty much true for a long time. It voids all warranty, no help from the brand (Lenovo in this case), has to be socketed, has to match the core logic chipset, has to be found somewhere as a spare repair part at high cost, is difficult to do, and may be rejected by the bios which has a secret approved list.
Intel® Core™ M-5Y71 processor is in one unit I see, with its built-in HD 5300 graphics.
Soldered to the motherboard and can't be replaced.
http://www.cpu-world.com/CPUs/Core_M/Intel-Core%20M%205Y71.html
That is the fastest one in the series
https://www.cpubenchmark.net/...u_list.php
Looking at the set:
M-5Y10 @ 0.80GHz2874
M-5Y10a @ 0.80GHz2540
M-5Y10c @ 0.80GHz2750
M-5Y31 @ 0.90GHz2484
M-5Y51 @ 1.10GHz3043
M-5Y70 @ 1.10GHz3065
M-5Y71 @ 1.20GHz3049
Even if you have a slower one, where you would replace the motherboard/CPU and whatever else is part of it, you don't gain enough performance to make it worthwhile.
In all of the laptops with the touch screen and flip-around type designs, that is what you are paying for.
You wanted the lightweight toy, and competitive systems are about the same.