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I need to replace the fan on my graphics card. The original fan is exactly like this one but there is another fan that seems to be a new revision of the same model number from the same manufacturer (NNTG vs. NNTM). The main difference seems to be the shape of the blades:

Neither I nor the DHGate seller can find any data about the fans (CFM, noise) so that's why I ask here.

To make up my mind I need an answer to both questions:

  1. Which blade design is likely to cool the GPU the most?
  2. Which one is likely to be the quietest?

The safe choice would be to get the exact same one (NNTG) but if the new design can be more efficient with the same noise, or as efficient but quieter, I'd prefer the new one.

Note that I don't want to buy an aftermarket fan (even if the prices are similar), I just want a replacement for the old one.

EDIT 2015-04-26 : Finally I bought both and, unlike what I said in the comments, I found a way to quickly switch the fan without taking out the whole heatsink assembly, allowing me to test both fans.

Despite the general consensus that NNTM was supposed to cool the GPU better, temperature with NNTG is actually 5°C cooler than with NNTM (after 10 minutes of running glxgears in full-screen). Maybe the motor doesn't match the power needed for the redesigned blades of NNTM, I don't know.

Anyway, if you need to replace a GA512SL fan for a RadeonHD like I did, buy the NNTG model :-)

MoonSweep
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2 Answers2

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Hopefully some helpful observations:

  1. Both fans have the same power rating
  2. Blade size differs I would have thought given the power rating this would equate to the smaller blades having a faster rpm, the larger blades can have a lower rpm for the same air flow.
  3. Rotational speed can be a factor in noise as faster generally equates to noisier, I say generally as not always the case. Larger fans generally have a lower rotational speed and produce less noise.

So to summarise I think both probably have similar air flow specifications, but the smaller bladed fan has a faster rpm, so is probably more noisy than the larger bladed version.

Air
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Ant
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3

Factors determining fan airflow (heat reduction):

  1. Blade pitch.
  2. Blade shape and size.
  3. Motor power and RPM.

In your case 3 is the same, 1 and 2 in the "newer version are bigger", so it will cool better. Main source of noise in fans is coming from the bearing and the electromotor (same in both cases) and from the blades which are slightly larger. Considering that our hearing works on logarithmic scale, I highly doubt that the increase of blades's size in the second model will double the noise, i.e. make it possible to discern from the first. Based on that, draw your conclusion :).

Ziezi
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