Chassis power cord burned, chassis burning plastic flavor, fan covered with dust, how to solve?

First thoroughly clean up the chassis and the power supply dust, conditions are best to use an air pump (air compressor) blowing, so clean up the most thorough, clean up the power cord to try, if it is not yet possible is the power supply burned, unplugged the power supply and the motherboard's main plug, and then short the green line to try the black line, if it can be started, then it may be the motherboard burned, if you can't start it is the power supply burned

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