I plan on building and installing a small computer in my car for multimedia purposes. Since the only space I have for it is under the passenger seat and since the temperatures vary between -20 to 35+ over the year, I am worried about condensation and any damage it might cause.
My first thought was to use a sealed case but not only they're expensive, they're physically too large as well. Since I can't prevent condensation, my only option is to decrease the likelihood of it causing any damage. I noticed that other electrical components in the car (radio, amp, etc) are conformally coated and I thought I might do the same. Hence, my question.
I read that such a coating could change the impedance of the PCB tracks or that it would hurt heat dissipation. As such, I am interested in knowing what components on a motherboard are safe to coat and how bad can these effects actually be?
For reference, the board I will use is an ASRock Fatal1ty B450 Gaming-ITX/ac, which, as far as I can tell, uses heatsinks for the chipset and the VRM.