That is called a "stress" blow. You are putting too much load on it and it simply will not handle what you are expecting it to do. It is kind of like a fuse, except instead of tripping a breaker, it simply ruins (they pop at times) the capacitors in there. You will be very lucky if it didn't also fry your motherboard and ram (or even more). I would find yourself a good brand name PSU and see what runs and what does not. Let us know if we can help you pick a good power supply and read
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