I have an Acer laptop with a dedicated graphics card GeForce 940MX, Core i5, but one single cooler (it's not a gaming laptop by any stretch of the imagination). It's thin, which causes little ventilation. My concern is that it is safe to run a game, say, like GTA V, in the long term? I already played GTA V a lot of times, and it gets very hot. Is it possible that some solder will melt on the motherboard in the long run? Every time I open GTA V to play I get afraid and paranoic about this.
All modern PCs have some means of protection systems that will prevent your machine from running in unsafe temperature modes.
You can check this shutdown on overheating thread on Intel's forum for the details.
So, you are safe, until you do some overclocking and deliberately disabled safety features.
P.S. If you are still paranoid, check metals melting points, they are mostly in hundreds degrees of C, so it's safe to assume that your motherboard soldering won't start to melt before your keyboard, which you would easily notice.