PSU Fan swap.

[small guy64]

So I have a NOS top of the line PSU from 2003 I'll be putting into a retro gaming PC. No, a modem PSU will not do. I need -5v and a higher 5v rail output.

The stock fan is a delta EFB0812EH 3 blade fan that is speed controlled. I want to put a better fan in it. I have a Arctic P8 that should work. But I'm on the fence whether or not to wiring it up to the stock fan port or just give it 12v. My though is that the speed controller in the PSU may not be tuned for the arctic fan and may not ramp up at the right times or speeds.

What are your thoughts.

 

Thanks.

[W-L]

7 minutes ago, small guy64 said:

So I have a NOS top of the line PSU from 2003 I'll be putting into a retro gaming PC. No, a modem PSU will not do. I need -5v and a higher 5v rail output.

The stock fan is a delta EFB0812EH 3 blade fan that is speed controlled. I want to put a better fan in it. I have a Arctic P8 that should work. But I'm on the fence whether or not to wiring it up to the stock fan port or just give it 12v. My though is that the speed controller in the PSU may not be tuned for the arctic fan and may not ramp up at the right times or speeds.

What are your thoughts.

 

Thanks.

Main thing is you want a pressure optimized fan in those kinds of applications. You can always probe the voltage of the minimum output of the current fan to ensure it has enough voltage to ensure the new fan has enough to start. 

 

Of course this always comes with the caveat of opening the PSU at your own risk as the capacitors in the unit can hold enough of a charge to be deadly and to ensure that you check the temps of the unit with a thermocouple of other temperature measurement device to ensure it's within safe operating temps. 

[small guy64]

22 minutes ago, W-L said:

Main thing is you want a pressure optimized fan in those kinds of applications.

The fan I have a arctic p8 witch is for rads and heat sinks so I'm good there.

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You can always probe the voltage of the minimum output of the current fan to ensure it has enough voltage to ensure the new fan has enough to start. 

Or I could cut out the middle man and plug the fan in?

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Of course this always comes with the caveat of opening the PSU at your own risk as the capacitors in the unit can hold enough of a charge to be deadly

Id take it you never played Hot capacitor? Its not what I would call deadly if the unit is off and unplugged, But still enough of a charge they to case injury or at the very lest make a good day do sour. Defiantly not for the untrained to mess with.

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and to ensure that you check the temps of the unit with a thermocouple of other temperature measurement device to ensure it's within safe operating temps. 

That I can do. I was hoping to get around that and just swap the fan and call it a day. I may just wire it up to 12v and be done with it now that I think of it.

[W-L]

9 minutes ago, small guy64 said:

The fan I have a arctic p8 witch is for rads and heat sinks so I'm good there.

Or I could cut out the middle man and plug the fan in?

Id take it you never played Hot capacitor? Its not what I would call deadly if the unit is off and unplugged, But still enough of a charge they to case injury or at the very lest make a good day do sour. Defiantly not for the untrained to mess with.

That I can do. I was hoping to get around that and just swap the fan and call it a day. I may just wire it up to 12v and be done with it now that I think of it.

I'd probe the leads to get the output voltage to verify the starting voltage is high enough before tapping into the connections for power since it's a speed controlled fan. You shouldn't need RPM line back unless the unit requires it for monitoring purposes. 

 

Just be cautious with the capacitors regardless at mains voltage it can be deadly. Unplug the unit and leave it for a good couple of hours incase before servicing and absolutely do not short the contacts of the capacitors. It's not the first situation where where's it's happened and also a situation like this happened on the forums where someone recounted their experience after opening a PSU unknowingly and making contact with a fully charged capacitor and ending waking up in hospital.

[small guy64]

12 minutes ago, W-L said:

I'd probe the leads to get the output voltage to verify the starting voltage is high enough before tapping into the connections for power since it's a speed controlled fan. You shouldn't need RPM line back unless the unit requires it for monitoring purposes. 

This a is a old school PSU, no RPM line. It has a voltage ramp, or so I believe that is what its called.

 

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Just be cautious with the capacitors regardless at mains voltage it can be deadly. Unplug the unit and leave it for a good couple of hours incase before servicing and absolutely do not short the contacts of the capacitors. It's not the first situation where where's it's happened and also a situation like this happened on the forums where someone recounted their experience after opening a PSU unknowingly and making contact with a fully charged capacitor and ending waking up in hospital.

I used to be a arcade machine repair man. The caps an a PC PSU is nothing compared to what I used to work with.

Try discharging a CRT's flyback. Those suckers ark, you only need to be near them in the wrong way to get a good zap.

[artuc]

Generally not advised.

 

I believe Jonny has raised this multiple times that a lot of the retail fans don't have the right specs for it, typically lacking static pressure and the fan speed is set on the PSU specifically for the fan used. (There was mention about Corsair tweaking Seasonic's fan choice/fan speed curve IIRC).

 

@jonnyGURU can jump in if I'm misinterprating here.

 

6 hours ago, small guy64 said:

I want to put a better fan in it

Delta make good fans, noisy but good.

 

Let's look at the specs:

 

Arctic P8

Fan 80 mm, 3.000 RPM, Fluid Dynamic Bearing
Airflow 23.4 CFM/40.3 m³/h (@ 3.000 RPM)
Static Pressure 1.9 mm H2O (@ 3.000 RPM)

 

Delta EFB0812EH

80mm, 5000RPM, Ball Bearing

Max Airflow: 52.2 CFM

Max Static Pressure: 8.9mm H2O

 

Looking at the graph at 24CFM static pressure would be 3.8mm(ish) H2O for the Delta. 

 

6 hours ago, small guy64 said:

My though is that the speed controller in the PSU may not be tuned for the arctic fan and may not ramp up at the right times or speeds.

What are your thoughts.

I mean I think that's pretty likely. It'll probably still work, just hard to tell how well, the Delta was picked for a reason.

 

Is noise the reason to consider replacing it ?

 

 

[Elisis]

7 hours ago, small guy64 said:

I want to put a better fan in it. I have a Arctic P8 that should work.

You're being quite confusing here. You say you want to put a better fan in it, but then you proceed to say that you plan to use an objectively poorer fan for this?

[small guy64]

2 hours ago, artuc said:

Is noise the reason to consider replacing it ?

Not quite, the delta runs at a rather low RPM on the built in controller and the PSU runs rather worm with it. Even under a load the fan hardly ramps up.

I could run it full blast but that would be loud. I ended up putting the P8 in it and wired it up to full 12v and so far my temp gun is seeing lower temps under a load.

 

Sorry for leaving that bit out. I'm bad at jumping into things and not explaining things well.