tx750m fan noise, is it a problem?

[Logifail]

Hi all,

 

Recently upgraded to a tx750m. My system isn't that power hungry so most of the time the PSU doesn't even need to spin it's fan. There is a normal quiet-ish whine from the PSU when moving the mouse but this isn't an issue.

 

When gaming (only Civ V, not that graphic hungry) the amount of power my system is drawing is right on the limit of the spin or not spin threshold for the PSU.

This causes the PSU fan to try to move a tiny bit but not put enough effort into it to move more than 1-2cm of rotation. As the temp builds and the fan goes into full spin mode the PSU becomes almost silent, as expected.

However the fan is so good that it soon cools down the PSU enough to go back into eco mode and make this horrible and quite loud 'almost spinning whine'.

 

I have taken a video of the problem so could upload it to youtube if that helps? not sure if it's ok to post links to vids on this forum?

 

Gaming for 4 hours+ the effect is the same and the PSU mostly just makes this noise.

To try and raise the temps in the PSU it has been turned over so the fan is on the underside, drawing air from the vent in the bottom of the case. This is much better when gaming as it seems to heat up more and so the fan spins more and is silent (from 1m away with the case closed) but now it makes the sound when just web browsing or other low load tasks. Though it's not as intense/loud as before (fan facing up and gaming) it's still louder than anything else in my PC.

 

I have tried the paperclip test and the fan does spin as it should, once spinning the fan is fine and makes very little noise at all, it's the non spinning part of the fan's function that make all the noise.

 

All the voltages for my system are good and stable, the PSU is supplying power properly.

 

Swapping back to my old powersupply eliminated the sound 100%. As my video shows (if it's ok to post a link?) you can see the fan is what is making the noise.

 

Running with an old gtx440 card the results are the same. Can't swap into another system for testing, did run with onboard graphics and results were the same.

 

With a temp probe at the exhaust vent of the PSU the temps reach around 37*c with ambient of 18*c. On light use these temps quickly drop back to around 24-25*c once the fan has finished spinning.

 

Reading these forums I found a number of other people having the same problem. This PSU was also bought as a 'Factory referbished unit' which means it's already been back to base at least once. (was supplied as new in original sealed packaging etc, bought from a scan.co.uk in the UK)

 

Does this mean that it's functioning properly and just makes a noise while doing so?

 

Sorry for the very long post, wanted to fully explain what's going on.

[jonnyguru]

Not normal and should be sent back to Scan.