Hi all,

I just bought a used custom-built computer locally. In the process of checking the hardware, I notice that the case fans have accumulated a lot of green "gunk" and I've tried wetting the edge of a paper towel to wipe and rub it off. Still, there is always some residue remaining. What's the best way to clean off this gunk?

Thanks in advance. No pictures, but I can take some if needed.