Clicking Noise near CPU Heatsink

[VicciVicVic]

Today I discovered a clicking noise near my CPU heatsink. It only occurs when it's under stress, however also occurs during a Unigine Valley benchmark which really only hits the GPU. When I start the benchmark there is a clicking noise that goes really quickly and then when I close the program it whines. I think it might be the fan but I can't see it being that as it whines too, and the fan is only 6 months old. I don't really know what it is but I suspect it is coil whine, but again I don't quite know so if any of you could help me that would be great.

 

[VicciVicVic]

Turns out it's coil whine coming from the GPU.