coil whine happens when a gpu runs at high fps, for example on a benchmark at 200fps it can happen, some do it at 120fps, it is variable
it is caused by a component on the power regulation stage on the gpu that under load makes that sound
some gpus are popular for having this happen
if you find it to be a problem, some manufacturers will change it for another gpu, but the new one might do the same
it depends on you if the noise is too high and unacceptable or if it is not a problem and you are ok with it