VOGONS


First post, by gilly76

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Looking to replace the case fan in my pentium desktop (currently has an Innovative model BP802512m, DV 12V 0.16A) which is quite loud. I tossed in a 120 mm case fan in to make sure it can run, and it's running fine, now I just need to get an 80 mm fan. The case fan is 0.08A, should I replace kind for kind here, or is it just a matter of pushing air (this is a P75 with just a heat sink on it, no active cooling over the CPU).

On that note, the power supply fan is loud (not as loud as the current case fan), is it possible (recommended) to toss in another fan that's quieter into the power supply? I also noticed the fan itself is pushing air out of the system, would it not be better for it to pull air into the system, or the fact that there's a case fan pulling in air it's better to push it out?

Reply 1 of 6, by Cosmic

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gilly76 wrote on 2022-09-22, 15:53:

On that note, the power supply fan is loud (not as loud as the current case fan), is it possible (recommended) to toss in another fan that's quieter into the power supply? I also noticed the fan itself is pushing air out of the system, would it not be better for it to pull air into the system, or the fact that there's a case fan pulling in air it's better to push it out?

I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It functions as both the PSU fan and blows over the otherwise passive CPU sink. It's much quieter and although the CFM rating was a bit lower, I didn't notice any issues.

If you go the Noctua route, definitely keep an eye on the CFM, as sometimes they achieve their quietness by pushing significantly less air.

IZbH9Zn.jpg

Reply 2 of 6, by Shponglefan

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gilly76 wrote on 2022-09-22, 15:53:

I also noticed the fan itself is pushing air out of the system, would it not be better for it to pull air into the system, or the fact that there's a case fan pulling in air it's better to push it out?

You want the PSU fan to be pushing air out of the system. This is because the PSU itself heats up, and you don't want to be pulling that hot air into your case.

Generally intake fans should be on the bottom/front of the case pulling in cool air, whereas exhaust fans should be on the top/back pushing out the hot air.

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Reply 3 of 6, by darry

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Getting one of those cheap temperature probes and monitoring PSU case temperature before and after the fan change could be an option.

If you get a PWM controllable fan and and a controller you could do some additional airflow tweaking for noise vs temperature .

If you're really motivated, you could probably build a temperature controlled, variable speed fan setup with a thermistor and a Raspberry PI (acting as fan controller https://www.digikey.com/en/maker/blogs/2019/h … he-raspberry-pi ) .

Reply 4 of 6, by gilly76

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Did you need to do any modifications of the Noctua for your power supply? Mine is a 2 pin setup, i'm guessing I could snip and solder the connector to the new fan, no?

Cosmic wrote on 2022-09-22, 17:41:
I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It […]
Show full quote
gilly76 wrote on 2022-09-22, 15:53:

On that note, the power supply fan is loud (not as loud as the current case fan), is it possible (recommended) to toss in another fan that's quieter into the power supply? I also noticed the fan itself is pushing air out of the system, would it not be better for it to pull air into the system, or the fact that there's a case fan pulling in air it's better to push it out?

I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It functions as both the PSU fan and blows over the otherwise passive CPU sink. It's much quieter and although the CFM rating was a bit lower, I didn't notice any issues.

If you go the Noctua route, definitely keep an eye on the CFM, as sometimes they achieve their quietness by pushing significantly less air.

IZbH9Zn.jpg

Reply 5 of 6, by waterbeesje

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gilly76 wrote on 2022-09-23, 01:35:

Did you need to do any modifications of the Noctua for your power supply? Mine is a 2 pin setup, i'm guessing I could snip and solder the connector to the new fan, no?

Cosmic wrote on 2022-09-22, 17:41:
I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It […]
Show full quote
gilly76 wrote on 2022-09-22, 15:53:

On that note, the power supply fan is loud (not as loud as the current case fan), is it possible (recommended) to toss in another fan that's quieter into the power supply? I also noticed the fan itself is pushing air out of the system, would it not be better for it to pull air into the system, or the fact that there's a case fan pulling in air it's better to push it out?

I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It functions as both the PSU fan and blows over the otherwise passive CPU sink. It's much quieter and although the CFM rating was a bit lower, I didn't notice any issues.

If you go the Noctua route, definitely keep an eye on the CFM, as sometimes they achieve their quietness by pushing significantly less air.

IZbH9Zn.jpg

Just see if the connector fits. You need red (+12v) and black (gnd) to be connected to the right pins to make the fan work.
All other pins (yellow, green) don't matter. Those are for advanced rpm and monitoring purposes and you simply won't use them 😀

If it won't fit due to the connector being too wide, you'll have to mod them...

Stuck at 10MHz...

Reply 6 of 6, by gilly76

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Just got both fans in this morning. Both fit with no modifications needed. So quiet, even quieter than my Windows10 computer (although to be fair that's running an RTX3700 (but otherwise water cooled).

I really need to get a desk for this computer so iIcan move it out of the dining room/home office and into the "computer room"

Thanks again for the suggestion

waterbeesje wrote on 2022-09-23, 08:55:
Just see if the connector fits. You need red (+12v) and black (gnd) to be connected to the right pins to make the fan work. All […]
Show full quote
gilly76 wrote on 2022-09-23, 01:35:

Did you need to do any modifications of the Noctua for your power supply? Mine is a 2 pin setup, i'm guessing I could snip and solder the connector to the new fan, no?

Cosmic wrote on 2022-09-22, 17:41:
I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It […]
Show full quote

I did this on my HP Vectra VL5 machine, Pentium MMX 233. I put in a Noctua fan to replace the original Delta Electronics fan. It functions as both the PSU fan and blows over the otherwise passive CPU sink. It's much quieter and although the CFM rating was a bit lower, I didn't notice any issues.

If you go the Noctua route, definitely keep an eye on the CFM, as sometimes they achieve their quietness by pushing significantly less air.

IZbH9Zn.jpg

Just see if the connector fits. You need red (+12v) and black (gnd) to be connected to the right pins to make the fan work.
All other pins (yellow, green) don't matter. Those are for advanced rpm and monitoring purposes and you simply won't use them 😀

If it won't fit due to the connector being too wide, you'll have to mod them...