Cool System Man.. :)

Another Fan Upgrade Story.

After updating my system with an ATI HD 5870 graphics card I wanted to reduce the system's internal temps. One particular area of concern was the temps that the hard drives were running at.

The plan was to increase the amount of case ventilation while not increasing the amount of sound produced by the system. I've been using Nexus fans for the CPU cooler and have been happy with the amount of air they move as well as the quietness of their operation but I thought I'd try some Noctua fans for this job. I've heard a lot of good things about them and this gave me a chance to see for myself if their extra cost over the Nexus ones was worth it. While the Noctua fans are around $26 each here the Nexus fans can be purchased in packs of 5 for about $50 or separately for around $12 each so given the Noctua's are about three times the price of the Nexus fans they'll need to be good to keep me happy.

The patient is a Q6600 based system with a Gigabyte 5870 Ultra Durable graphics card and three Western Digital hard drives powered by a Seasonic 500W S12 power supply. This is all housed in a CoolerMaster Centurion 532 case. The system's been running happily for a long time with just the cases' stock intake fan sitting in front of the HDD cage and the rest of the ventilation being taken care of by the power supply's fan. That intake fan is a clear plastic CoolerMaster 120mm one which used glow blue when the case was new but the LEDs have since failed.

This setup was adequate for the system previously but with the nVidia 9800GT being recently changed out for a more powerful HD 5870 which is now dumping more heat into the case than did the 9800GT I felt it was time to do some ventilation upgrades.

The plan was a pretty simple one. Add a rear case fan for evacuation of hot air and also increase the amount of air brought into the case by the HDD fan. I was hoping that a side benefit of the rear fan would be that because not so much hot air would be passing directly through the power supply it would operate more coolly and therefore more quietly.

Fan selection is as follows. As I wanted a greater volume of air over the hard disks and because the drive cage presents more of an air restriction than does everything else I went with a Noctua NF-P12 High Pressure fan. These are often used as CPU cooler fans and better fit the role as HDD cooler fan than does a low pressure one for this case. As the rear vent fan wouldn't need to be so forceful as the HDD one I went with a lower pressure Nocuta NF-S12B for this.

These Noctua fans come with a 6 year warranty in addition to the various other bundled goodies.

Before replacing the intake fan I took some temperatures and the results are as follows:
(Values as reported by the drive S.M.A.R.T. data.)

Temps are expressed as “degrees Celsius above current ambient temperature.”

Degrees Celsius above current ambient temperature
Old Fan @ approx 1500 RPM

While I was recording the temperatures I also recorded the sound of the old fan. For later comparison.

After recording those numbers it was now time to replace the original CoolerMaster HDD cooling fan with the Noctua one.

Here's the contents of the NF-P12 package.

  • The 120mm fan (1300 RPM standard.)
  • 1100 RPM speed reducer.
  • 900 RPM speed reducer.
  • Fan connector to Molex adaptor.
  • 4 Fan screws.
  • 4 Vibration isolating soft mounts.

One benefit of purchasing higher end fans is that they include the various odds and sods to get the fan mounted and connected to the system.


The NF-P12 speed reducers.
One for 1100 RPM operation and one for 900 RPM operation.
I went with the 900 RPM one.

It's nice that they include fittings to get the fan mounted. Not everyone has these lying around.
I used the soft mounts.


The CoolerMaster fan was mounted with normal fan screws but I chose to mount the new one with the bundled soft mounts.

Out with the old,

The original fan saw many hours of reliable operation.
(except for the LEDs.)

and in with the new.

The way the drive cage is made the two bottom drives get most of the fresh air.


Now to run up the system and get the new temperatures. First numbers are with the fan running at its stock speed of 1300 RPM.

Degrees Celsius above current ambient temperature
New Fan @ approx 1300 RPM

There's a decent drop in temps which is good given the expense and effort to replace the old fan.

I recorded the sound of the new fan at this point as well. When I compared it to the older fan recording it was a bit louder now than it was before. It also had a different note as well as being louder. I liked the cooler temps but wasn't thrilled with more sound.

Time to try the new fan with the 900 RPM speed reducer. Here's the temps with the slower speed.

Degrees Celsius above current ambient temperature
New Fan @ approx 900 RPM

The temps were only very slightly increased at the slower speed but still lower than those with the old fan. Thankfully it also seemed quieter at this speed than the old fan as well.

Before I add the rear exhaust fan there's something else to do. Clean the front air filter. It should be interesting to see what if any effect this will have on the temps.

Before: Yuck!

After: Nice and clean and able to breath.


Degrees Celsius above current ambient temperature
New Fan @ approx 900 RPM with clean filter.

Here we have a drop in temps of a similar magnitude to that of the adding of a better fan. As well as the better temps with a cleaner filter it also seemed a little quieter.

Degrees Celsius above current ambient temperature.

Looking at all of the temperatures together there's a strange change in the order of which of the two bottom drives is the hottest. I'm not sure why this changes due to air speed differences but there you have it. That aside the end result of the changes is a pleasing drop in the HDD temperatures and demonstrates that the Noctua fan is more effective than the stock CoolerMaster fan even though it's running at a slower speed.

Looking at the temp drop due to simply cleaning the air filter it seems that its cloggedness was the biggest impediment to coolness. In the future cleaning air filters would be the first thing I'd try.

So here's the recordings of how the two different fans sound. I was surprised to find that to me personally, the sound of the CoolerMaster fan seemed better than that of the Noctua. Certainly better than the Noctua running at 1300 RPM and only just very slightly better when the Noctua is at 900 RPM. With that said the Noctua is more effective at its primary role which is to cool. The sound recordings were made at a distance of 5cm from the fan and seem much louder than they actually are at normal listening distances.

Very fan-ny sounds.

The effects of the addition of a rear exhaust fan will be posted shortly.

Copyright (c) 2010 Greg Newsome all rights reserved.