>The only way to do this reliably and without fire hazard is to passively cool the hardware completely by having HUGE heatsinks and THEN you can add a fan that

>The only way to do this reliably and without fire hazard is to passively cool the hardware completely by having HUGE heatsinks and THEN you can add a fan that you slow down with a resistor. Sized appropriately, you can do it 100% passive and still maintain lifespan. You'd only need a fan if your ambient temps exceeded design specs. There are a lot of things you can do to optimize your thermal design / minimize sink size: - Choose a better sink material (like copper) - Sink fin design (# of fins and spacing) should be designed for natural convection - Maintain proper device/sink orientation (standard fins should be perpendicular with the ground, pin fin style sinks can be vertical or horizontal) - If you've got a huge heat sink, you can employ vapor chambers or heat pipes to serve as heat spreaders to improve utilization of the sink / reduce spreading resistance. - Use the best thermal interface material you can afford - Apply the most allowable contact pressure between your components and your sink to reduce thermal contact resistance Shameless plug... our company sells fanless servers for industrial applications (https://lanternedge.com/ https://lanternedge.com/)