Dell Optiplex 7040 micro CPU Fan Replacement

[linux_admin]

Hello everyone, I would like to replace the super loud blower fan my 7040 micro has, saw part of the front plate off and stick in a Noctua NF-A6x25 PWM 4-Pin 60mm. The noctua fan has the standard 4 pin interface but the Dell machine uses their proprietary nonsense interface. They don’t support pinouts for any of their devices and have a proprietary wire layout.

Is there any type of adapter i can use without having to get a USB to 4-Pin 5V Adapter Cable or having to cut the wires and make a custom breadboard myself?
I saw something like this on amazon but i’m not sure if the wires are even the same order or if it even fits.

Thank you!

[gordonthree]

Cut the connector off the old fan and solder the wires onto the new fan. Use a multimeter to confirm you’re picking up the 12v and connections.

[TheAlmightyBaconLord]

Was thinking the same thing. You can easily find out what 12v and GND is on the original fan cable. Then simply guess which is Tacho and which is PWM for the other 2 wires. If you flip Tacho and PWM, nothing bad will happen to the system or fan, but the fan will run at max speed once powered on. Simply flip Tacho and PWM connecions, and the Dell motherboard will be none-the-wiser that you replaced the fan.

[linux_admin]

Seems like that’s the only option, hope the noctua fan won’t be too loud at max rpm. Why Dell, whyyyyyyyyy

[GigaBusterEXE]

before you go permanently chopping up your computer, have you tried replacing the thermal paste and undervolting with an old version of XTU

also plug the noctua fan into a 12v source to even see if at max speed it will even keep it cool

[Zavar]

I’m surprised it’s loud. The Optiplex I had was pretty quiet, and had the same fan setup. Like giga said, assuming you’ve repasted before doing that?

Also worth keeping in mind the old shroud and fan directed air over the VRMs as well, and you could run into power limit throttling issues in sustained loads if dell’s using lower capacity mosfets.

[GigaBusterEXE]

on my haswell system I was able to shave off 100mv safely in offset mode on XTU

if you have problems with undervolting via XTU or throttle stop refer to post #23 (ctrl+F 23)

Cannot undervolt with either ThrottleStop or Intel XTU

[luiceur]

Would it fit the cooler of a Noctua NH-L9i? That might be enough in most cases. I am actually trying to upgrade the fan/cooling system of my Optiplex Micro. Any success on this?

[AveryFreeman]

I’m sure there’s a cable adapter for a fan out there, why not just get a bigger 5v fan?

I got a stack of five 7050 micro motherboards for $50, slowly making machines out of them.

So far, I’ve put one in a cheap af 3020m case shipped from China, fits great (just had to chop away metal around DSUB connector hole to make way for HDMI)

Side tip: oscillating tool + carbide blade for cutting cases is way better than Dremel cutting wheel, and there’s no sparks! (YOU know what I’m talking about…)

I’ve got a model 5JV3N just like you, but wanted to see if I could shove a 65w processor in this thing. Have a 130w power supply on the way, scheming about how I might be able to drill holes in the housing and pry a 14cm fan in somehow…

Another idea was trying to find a laptop sata connector to power adapter (the only power I can see on board besides fan) keep the old fan and add a pancake blower in there.

Just thought of one last idea - definitely easiest yet. Get one of these and stick it pointing into the case, blowing like hell - no need to mod anything! (Kinda less fun, but…): https://www.amazon.com/gp/aw/d/B08MZB97P3

Would look kinda cool with an assload of poorly drilled holes and a 14cm fan, though…

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