Discuss modifications you have done or plan to do to your Dreamcast or any other hardware, or discuss devices you want to build. If your console does not work or is acting up, ask about fixing it in here.
I was just scaning over the boards and ran across this topic. It's easy, just grab a 12V fan out of a computer (power supply fan is what I used), then run wires from the DC power board out to the fan and presto! :D Its not mounted and it's not the prettiest, but it works.
I doubt that external fans work, coz not much room for air to circulate, I would recommend you making a heat sink that could reach outside, and then cool that fro outside, making the heat from inside move faster to the outside, making the heatsink keep absorbing more and more heat all the time