Laptop: Acer Aspire 5742g
dGPU is GT520m
I’ve been trying to make this laptop’s discrete GPU to work for the past three days to no result.
[The only driver version supported by gpu is 390xx]
Tried using Hybrid Bumblebee drivers - black and white stripes with a cursor and no access to TTY2.
Tried installing linux69nvidia390xx (I forgor the exact package name) through terminal and GUI. Optimus didn’t work no matter if I set it up manually or through envycontrol.
I don’t want to use iGPU at all, cuz my brother is always uses it on a charger, so power consumption is not a problem. All that I ask of this laptop is to play Minecraft beta with more 15 fps.
More specs:
i3-380M
3GB of RAM, because I had to swap one of the sticks. Originally it was 4GB, I think.
Hello @NEPHILIM 
The problem though is that the dGPU is not physically connected to the monitor, and I doubt that the laptop has a physical switch. Those laptops use a redirection technique over CPU.
v390x has no support for optimus, so you would need to use bumblebee: Bumblebee - ArchWiki
Note that nvidia-xrun - ArchWiki is also an option.
That’s the problem, as soon as I install Bumblebee, KDE ■■■■■■ itself. Well, after a reboot that is.
Should I TimeShift, install Bumblebee driver and without rebooting configure nvidia-xrun?
Note that bumblebee is still an unofficial hack from times when optimus was not implemented in the Linux driver, so v390xx and below. It uses VirtualGL to render frames, and probably KDE is not compatible these days.
Do as you please.
The only thing that is gonna please me is someone giving me a hand, cuz I’ve been using Linux 4 days and I be stupid
Well, I gave you links to the Arch Wiki, which describe it pretty good.
Start for example with asking more specific questions to the process. I don’t know what level of knowledge you have, and I don’t want to repeat what is already written. Either way, you need to read, understand and learn, there is no way around.