Solved Noisy OCZ ZT750 Power Supply Fan - fixed

[fireberd]

FYI.

ADDED I guess I shouldn't say "fixed" but rather the fan noise is acceptable mounted with the fan up.

I recently built a new PC and used the OCZ ZT750 power supply. I mounted the power supply with the fan down (it mounts in the bottom of my Corsair Carbide 500R case) so the 24 pin and 8 pin cables for the motherboard could be routed to the rear of the motherboard for a cleaner cable install. There is a filter screen on the bottom of the case so there was no real air flow restriction. However, the power supply fan was extremely noisy and about 10 seconds after powering on, the fan would spin up to max and never change. It was too noisy for my application - the PC was built for my recording studio.

I decided to reverse the power supply mounting, and mount it with the fan facing up. Surprise, the fan quieted down to a very acceptable level with the case covers installed. I will now have to route the motherboard power cables in front, but at least the power supply fan is at an acceptable level.

 

[ignatzatsonic]

What is your speculation on why flipping the PSU made a difference in noise level?

I've heard of some fans having different lifespans if mounted vertically rather than horizontally, but can't recall any comments on noise levels. And you stayed with horizontal in any case.

I'm wondering if getting the fan away from that bottom vent on the case made the difference?? Maybe what you were hearing was air turbulence through the vent as opposed to fan noise per se?? They tell me that cutting away those honeycomb vent structures can reduce turbulence noise, but I've never tried it.

 

[fireberd]

I don't know for sure. But, with it mounted with the fan down about 10 to 15 seconds after it was powered on the fan would speed up to max and stay there - never change. With it mounted with the fan up, it still speeds up after about the same amount of time, but its not full speed and the fan noise, with the covers on the case, is tolerable for my recording studio.

I've opened a support ticket with OCZ and I'll see what their support says about this.

 

[fireberd]

OCZ is going to replace the power supply.

This is what I got from support:

I am sorry for the problem with your power supply. We have noticed that some of these units have a faulty component in the fan controller that can cause fan speed problems. Your replacement will be a newer unit with a different component in the controller

 

[ignatzatsonic]

That's good that they are accommodating.

Keep us updated on how painless and quick the RMA process is.

 

[fireberd]

I'm supposed to get a UPS shipping label so the return shipping will not cost me (+1 for OCZ for that).

I have a new power supply scheduled for delivery tomorrow, for a new PC I'm building. I'll use that power supply until I get the replacement OCZ power supply. The new PC I'm building doesn't have to be done until late September so borrowing the power supply won't be a problem.

 

[fireberd]

I got the UPS shipping label overnight. I'll ship it out today. I'll see how fast OCZ's turnaround time is. As I'm in Florida and they are in California it will not be a quick deal.

 

[fireberd]

The replacement OCZ power supply came in today. Its quiet, as its supposed to be.

It did take two weeks (one week to get it from Florida to California and another week to get from California to Florida). If it was an operational system that was down for a part, two weeks would be unacceptable. But as I had a spare power supply to use there wasn't any downtime.

Jack