Switching 6 pin and 8 pin power source - vibration from PSU with GTX 970

[nine9s]

I went from a GTX 680 to GTX 970. I started noticing a stronger vibration/low hum from my computer. I narrowed it down to PSU (touching it, I could feel the vibration matching the low hum.) Since the 970 uses less power than the 680, it seemed confusing why this would happen (seems it would be easier on the PSU.)

Anyway, my PSU is module and the two cables, I use for my video card, are two 6+2pin connectors. At first I was going to just plug them into different slots on PSU, but I decided to just switch them on the card. Vibration went away.

What would cause the vibration in PSU from the initial 6+2 slots I used?

 

[toyota]

I think every psu I have used has had a little vibration going through it. I can touch or push on it and will stop for the time being but will always come back. the case makes no difference either. I only can notice it from the back of the pc and even then I have to listen for it or put my hand back there to feel the slight vibration. after 3 psus and 3 cases I assume its normal. lol

 

[nine9s]

I was just curious about the situation of it seeming more pronounced in how I used the two 6+2 pin cables in the 8 and 6 pin slots in the card versus how it vibrating after switching them around.

 

[toyota]

maybe just the fan on the psu is running a bit different rpm now? and depending on the exact 970, it uses about the same power as the 680 or more. some even use as much as the reference 780 so dont be fooled by the TDP claims. those were purely for marketing.