Why does the Zalman ZM600-GSII smell like it's burned?

Question

Iron

From the Zalman ZM600-GSII PSU it smells like it's burned. The smell is not strong, but noticeable. He himself does not seem to get warm, the computer works fine. Bought in DNS somewhere 6-7 months ago. When I bought and installed the smell was (but it seems to be normal for a new one), then the smell disappeared, now again. Zalman is also on another computer, he is 4-5 months old, the smell is also not strong. What is the problem?
Added
Could it be because my video card will soon be closed? Those. can she influence it?

Answer 1

Dust sucked, it is heated there and smells. Or maybe the board is overheating slowly. An autopsy will show.