Umm... this section is not actually about THOSE kind of fans. It's about art created by people who like a series, not creating artistic designs on computer fans. Well, unless we're talking about painting Zelda characters onto a computer fan, or something, then it might apply.
But anyway, as to your question. There might be an option in the BIOS as to what temperature to set for the fan to come on. You would have to check documentation for your specific BIOS. If you set that temperature much lower than the processor's normal operating temperature, the fan will run all the time.
Failing that, you can open up your computer and disconnect the fan from the temperature sensor (while leaving it connected to the power). On most computers, doing this will cause the fan to run all the time.
A lot of this will depend on your specific computer, so we will need more information. Sorry if this answer isn't too helpful.
I will ask, though, whether running the fan all the time is the best choice for fixing this problem. You might be better off getting a video card that runs cooler. Laptops weren't really designed to run high-powered devices that generate a lot of heat. You may need a desktop computer for your video needs, if a high-end card is required.