Just, as a test cool the cpu with a external fan.
If that works, build one in it.

However when you build a fan into a dm800hd, do not use the fan connector because it ballast the voltage circuit.
Better is to connect a 12v fan to the 12v input connector and to reduce the speed use a dc to dc converter or build a fan controller by yourself.
See google with searching to fan controller schematic.
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Doing nothing leads to nothing.

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Johnny B.

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