JonHimself said:
PS - If the answer is to "flash" something please keep in mind I only have a slight idea as to what that entails....
There's a "non-volatile" flash rom chip inside the computer -- kinda like a compact flash or SDRAM card that goes in a digital camera -- that holds some information that is loosely a mix of programs that are used right at the beginning to get the computer working, when you turn it on, and preference type of info related to these programs. This information can be modified, but it is persistent when the computer is turned off, unlike RAM.
I believe there is another ROM chip (or a portion of the same chip), which has a copy of what is in this "flash" ROM chip, as well as other stuff, but this ROM chip is not "flashable" -- you can not change its contents.
The "flashing" basically means...to enable the hack, you use a program to write part of the flash ROM to different values that tell the graphics card to allow spanning. To get rid of the hack, you tell the computer to copy over the flash ROM from the permanent ROM back to its original value. You do this by holding some keys on startup. Not too hard.... In principle, things could get so messed up that even this function is not possible, or some damage is done that prevents the computer from working correctly even after this is done.... That's the risk you take.
Running software and voiding the warranty is sort of like operating a car. You expect the car to work properly when you use it properly. But, for instance, if you drive a car in second gear constantly and keep the engine near the redline for hours at a time, the damage you cause may not be covered by your warranty... If you were, say, for the sake of argument, to run a program that disabled your computer's fan and ran the CPU and the HD as hard as it could, and it caused your motherboard to melt, well....
😀
But there are few reports of anything like that happening with the spanning hack....