I'd have the pelt PSU and pump wired into the same plug as the PC, so if one fuse goes they all stop kinda thing. I'd use a relay for the pump & TEC as well (the TEC does'nt need to be turned on before does it?), so if the PC shuts down so do they. if the TEC fails or the pump the PC should auto shutdown should'nt it?, MBM5 has this even if the native hardware monitor has'nt...
PS. Don't get me wrong, I love a wacky experiment as much as the next geek

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