LuciferTechWizz

You have to be really careful that no liquid metal gets anywhere exept the gpu/cpu die. I used normal thermal paste to isolate the components around the die, to ensure that the liquid metal stays where it should be.

Arduino uses an 8 bit  microcontroller , it's not a processor. 
 
You could create a custom circuit board that you could insert into  a PCI slot or PCI Express slot in order to take power from those slots, but communicating with the computer through those slots is very complex (it would take a lot of code to do it, maybe so much that the microcontroller may not have enough built in memory to store all that code)
You could add a SPI/i2c/UART to USB chip (serial communication) on your custom arduino board and them connect the USB created by that chip to one of the USB 2.0 headers and then your arduino could talk to the computer using serial communication, so software on the computer could send and receive data from your custom arduino board
 
When you're ready to go a step above Arduino, there are microcontrollers like PIC18 and PIC32 which have USB functionality built in and which is fast enough (can do a few mbps in both directions) which makes it possible to do neat things with them.
 

Yes sorry, I use the dark mode and I didn't checked (text is white in dark mode so I took the closest colored color, I'm a idiot )
Changed it
 
I actually have the same problem with the blue color which is almost unreadable, but as many people use the light theme (and blue is not widely used) I just select the text to read it.

That is a VERY sharp color which makes the post unreadable and bothers what I believe most people on the forum. Do not take this as an insult, just a constructive critic.
 
Cheers!