Psu fan swap, new fan wont spin.

[Bupalooga]

So I'm building a pc and i swapped the fan on the PSU (Silverstone SFX SX650-G)  for a Noctua A9x14 and now its not spinning at all!

I had it up and running just fine before the swap but the fan span all the time and was louder than the rest of the computer (all Noctua) which is why I decided to swap it for a quieter fan.

 

Even at full load (230 watts from the wall) the fans not even trying to move!

 

So unless power and ground wires were color coded wrong in the psu (I put black - black & red{psu} - yellow{noctua}) and ideas on what the problem could be? am I missing something?

 

The only thing I found weird is the psu stock fan is 12v 0.45amps, which is 4 times the Noctuas amperage. But that would mean the noctua is easier to spin so I dunno.

Assided ×

[PopsicleHustler]

I've messed up badly, thats all I can say. That stock PSU fan uses simple 12v DC to operate, PSU controls its speed by changing the voltage.  Noctua fan on the other hand is using PWM signal to operate, hence why it won't run on a simple 12v DC.

[Stefan Payne]

13 minutes ago, Bupalooga said:

So I'm building a pc and i swapped the fan on the PSU (Silverstone SFX SX650-G)  for a Noctua A9x14 and now its not spinning at all!

Oh my god, why the heck did you do that?!
Here what a "Professional" says about replacing the Fan, quoted from another Forum:

 

Quote

We have a number of people, especially in EU, that replace the stock SF fan with Noctua's 92mm fan.  We've done the same and have found that while it is quieter at lower loads, it cannot support proper cooling at higher loads and is actually louder at those loads (despite not being able to keep up).

PSU companies don't tend to "throw whatever fan fits" into a PSU.  End users often do tend to think they know best, but that typically back fires on them unless they're running a corner case.

jonnyGURU Forums - View Single Post -  SFX: Silverstonetek SX700-PT, any guess how it will compare with SF600?

 

@jonnyGURU Is product manager at Corsair right now, he knows a bit more than most people.

Not only did you replace the fan with a totally inapropriate one, you also mounted it the wrong way!

There is a reason why it blows inside and not out!!

 

If the fan was broken, you could have used the RMA - wich is no longer possible as you voided it...

Quote

I had it up and running just fine before the swap but the fan span all the time and was louder than the rest of the computer (all Noctua) which is why I decided to swap it for a quieter fan.

Yeah, who cares about the specifications of the Original fan and why it was there and what it did...

There was a REASON why those fan was used!
 

With replacing the fan you change the specification.

Not only that, you might even cause a fire...

[Bupalooga]

1 minute ago, PopsicleHustler said:

That stock PSU fan uses simple 12v DC to operate, PSU controls its speed by changing the voltage.  Noctua fan on the other hand is using PWM signal to operate, hence why it won't run on a simple 12v DC.

I thought pwm fans could still work fine on just voltage control. That's why they still work on 3 pin fan headers dont they?

[Bupalooga]

4 minutes ago, Stefan Payne said:

Oh my god, why the heck did you do that?!

 

Because its the loudest part of the computer.

I wasn't worried about the specs of the fan, I was just trying to make it quieter at idle. And that all it did, it idled loudly and never ramped up after continual pc stress testing.

 

I mounted it the other way because it works better with the entire system airflow since there's a fan pointed at its side "exhaust" vent

[Guest]

10 minutes ago, Bupalooga said:

I thought pwm fans could still work fine on just voltage control. That's why they still work on 3 pin fan headers dont they?

Wrong.

 

Headers on motherboards that support both PWM and DC are designed to support both.  PSU fan controllers aren't meant to be "universal" like motherboard fan headers.

 

You messed up big time.  If you wanted a quieter PSU, you should've bought a quieter PSU.  Your best bet right now is to just put the original fan back in the PSU.

 

And put it back in the correct way.  While the entire system's airflow might be better with the air blowing out of the PSU, you risk the PSU overheating.

 

 

[Bupalooga]

1 minute ago, jonnyGURU said:

Wrong.

 

Headers on motherboards that support both PWM and DC are designed to support both.  PSU fan controllers aren't meant to be "universal" like motherboard fan headers.

 

You messed up big time.  If you wanted a quieter PSU, you should've bought a quieter PSU.  Your best bet right now is to just put the original fan back in the PSU.

 

And put it back in the correct way.  While the entire system's airflow might be better with the air blowing out of the PSU, you risk the PSU overheating.

 

 

Bugger!

O well, ill just have to pop the other one back in and put up with it I guess.

[Stefan Payne]

Just now, Bupalooga said:

Because its the loudest part of the computer.

Then replace it with a quieter PSU!

There is no other way!
YOU do not have the legal requirement to work on a PSU!
And the PSU is not certified.

 

IF something goes wrong and the fire in your house is linked to what you did, no insurance will pay and you might even go to jail!

 

Just now, Bupalooga said:

I wasn't worried about the specs of the fan, I was just trying to make it quieter at idle. And that all it did, it idled loudly and never ramped up after continual pc stress testing.

Yeah and cause the PSU to overheat...

Great idea...

You know its rather high RPM for a reason?

 

So, while I was looking for a Datasheet, I found something vaguely Similar:
RL xx S0921512HH (not the HB), wich is 12V/0,4A - close enough.

And rated for 3500rpm.

The fan you chose has only around 2200rpm - so there are 1300rpm missing.

But that's not the important stuff...

 

That is the Airflow - wich is vaguely similar, BUT: The Airpressure is not!!

And here we're talking about 3,2mmH²O vs 1,64mmH²O...

That's about half.

And the Static pressure is very important when blowing against a wall...

 

 

Besides that:
PSU usually work with 3-4V minimum - PWM fans do not work with such low Voltages at all. 5-6V is the Minimum for those.

 

Just now, Bupalooga said:

I mounted it the other way because it works better with the entire system airflow since there's a fan pointed at its side "exhaust" vent

...and cause the PSU to overheat even more...

 

Sorry, but you done goofed.

Put in the old fan and save for a QUIET PSU, wich is not really possible in SFX as there is just no space to put the Heat(sinks). Its a compromise and you trade electrical performance and especially quietness for size.

[Bupalooga]

6 minutes ago, Stefan Payne said:

YOU do not have the legal requirement to work on a PSU!

Yea naa, laws must be a little different where your from.

 

I had no intentions of limiter bashing the psu so I was fine with sacrificing some of that top end cooling performance.

 

But it don't work so back to stock I go.

[Guest]

40 minutes ago, Bupalooga said:

Yea naa, laws must be a little different where your from.

A PSU has lethal voltages stored in the bulk cap and potentially a live primary heatsink, so it's not a good idea to work inside them and if you kill yourself in the process, you (or rather, your next of kin) have little recourse to sue anyone.

[Bupalooga]

1 minute ago, jonnyGURU said:

A PSU has lethal voltages stored in the bulk cap and potentially a live primary heatsink, so it's not a good idea to work inside them and if you kill yourself in the process, you (or rather, your next of kin) have little recourse to sue anyone.

Yea I knew that bit, keeping my clubbed thumbs out of all the zappy bits.

 

Whats with the rest of the world and and they're addiction to suing each other. Take responsibility for where you shove your fingers, if not get back in your padded room lol.

 

But thanks for explaining where I went wrong tho.