[SOLVED] CPU fan absurdly loud

[Insane Potatoz]

Hey everyone. I recently bought a used combo that included a motherboard, i5-2400, a cooler, and 4gb ram. So I took the ram out and replaced it with 8gb, and threw a GTX 650 TI in there so I could see if it boots up.
I got it to get into the BIOS, but the CPU fan is crazy loud. It sounds like a helicopter taking off in my room. I couldn’t find a setting in the BIOS to adjust fan speed. Anyone know how I’d fix this?

 

[anotherdrew]

@Insane Potatoz
Really hard to say. Is the fan spinning so fast because the CPU is running hot or maybe is it locked at full speed by BIOS for some reason. Or could it be the fan bearings are shot and not running fast, but it sure sounds like it. It would be nice to know the motherboard model number, CPU temp, Fan RPM, etc.

 

[Insane Potatoz]

@Insane Potatoz
Really hard to say. Is the fan spinning so fast because the CPU is running hot or maybe is it locked at full speed by BIOS for some reason. Or could it be the fan bearings are shot and not running fast, but it sure sounds like it. It would be nice to know the motherboard model number, CPU temp, Fan RPM, etc.

Not sure of fan RPM. Doesn't show in BIOS
I've tried 3 different fans on this CPU.
Not sure of CPU temp either. It's for a PC flip and I'm waiting on the drive to arrive so I can download windows on it and maybe look at stuff from there.

https://www.ebay.com/itm/Dell-0GDG8...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2648
This is the exact thing I bought except I replaced the RAM with 8gb

 

[SkyNetRising]

Boot into windows. Fan speed should go down.
In BIOS it may be running at max speed.

 

[Insane Potatoz]

Boot into windows. Fan speed should go down.
In BIOS it may be running at max speed.

Alright I'll get back to you guys when I get the hard drive and windows installed. CPU fans have never been loud when I'm in bios before so that's why I'm worried.
Hard drive should get here on monday

 

[anotherdrew]

Alright I'll get back to you guys when I get the hard drive and windows installed. CPU fans have never been loud when I'm in bios before so that's why I'm worried.
Hard drive should get here on monday

So it's a Dell motherboard. OEM motherboards are notorious for lack of options (keep it simple for the masses). That's how it is and I'm sorta ok with that. Yes, booting into an OS might bring the fan speed down. We will see ... let us know.

 

[Insane Potatoz]

Alright sorry for taking so long. I have windows installed on the machine. The fan gets quiet, but whenever the CPU gets around 20% load the fan will ramp up super loud again. Any idea how to fix it?

 

[Insane Potatoz]

Is there a way to possibly control the fan with speedfan? I installed it on this PC but I'm kinda confused as to how it works...

 

[Karadjgne]

Ahh, have to be careful with Dell motherboards. They are proprietary and some motherboards are wired backwards, to try and prevent upgrades from non Dell sources.

Reason why you can't see speed is its probably not hooked up right, wires are crossed. You'll need to verify against the original or use a multimeter to test thoroughly.

https://www.dell.com/community/Optiplex-Desktops/Optiplex-3010-MT-120mm-fan/td-p/6127118

 

[Insane Potatoz]

Ahh, have to be careful with Dell motherboards. They are proprietary and some motherboards are wired backwards, to try and prevent upgrades from non Dell sources.

Reason why you can't see speed is its probably not hooked up right, wires are crossed. You'll need to verify against the original or use a multimeter to test thoroughly.

https://www.dell.com/community/Optiplex-Desktops/Optiplex-3010-MT-120mm-fan/td-p/6127118

This has a standard 4 pin connector. And the fan that came with the motherboard does the same thing.
Here's the link to what I bought: https://www.ebay.com/itm/Dell-0GDG8...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2648
You can see it has standard 4 pin connector for the CPU and 2 3 pins for case fans (Which are occupied)

 

[Karadjgne]

Maybe so, but it depends on the placement of the wires, not the actual connector, as shown by that 3pin wire picture. The 12v wire and tach wire are backwards to what universal aftermarket wires use.

 

[Insane Potatoz]

Maybe so, but it depends on the placement of the wires, not the actual connector, as shown by that 3pin wire picture. The 12v wire and tach wire are backwards to what universal aftermarket wires use.

hmm. Well the fan that came with it does the same thing.
Here's the wire colors from left to right
On the fan i'm using now: Black - Red - Yellow - Blue
On the fan that came with the board: Blue - Yellow - Red - Black
And both of them had the same issue... at least in the BIOS. I haven't tried the one that came with the board in windows...

 

[Insane Potatoz]

omg wait. Blue Yellow Red Black is the right pinout right? So I'm going to install the one that came with the board and see if it works. Sorry for being in idiot. I'll get back to you later if it works.

 

[Karadjgne]

Exactly. Wires are backwards.


What you'll have to do is use something like a mechanical pencil and push down on the spring in the little slot on the back of the connector. Then slide the pin out. When all 4 are out, line them up exactly like the original wiring.

 

[Karadjgne]

Standard pinout would be black-yellow-orange-blue, that's ground-12v-tach-pwm.

Thats what's on any of the new fans. That's what needs to be changed or swapped to match the original factory Dell fan, so the connector sits correctly and the wires line up with what they need to be, ground to ground, 12v to 12v etc.

Dell does some funky stuff, it makes sense to them even if it doesn't to us.

 

[Insane Potatoz]

Alright yeah I think I got it. I put the normal fan back and have made a custom fan curve using SpeedFan for the CPU cooler. Thanks for helping a brainlet like me XD

 

[Insane Potatoz]

Okay new problem lol. I guess this could just be me being dumb but I don't think so.
So I went to stress test the CPU and it got really hot. I so into SpeedFan and notice that the fan is only at 50% speed. Long story short, my fan curves won't work. Also, the fan is either really loud or too slow.
If i set the Speed to 66% or lower, it'll be 700-800 rpm no matter what. When it's set to 67% or more it'll be 3000+ rpm no matter what. This is enough to cool the CPU but it's loud and obnoxious. Do you know ow any way to fix this?

 

[Karadjgne]

You'll probably need to dig into those fan curves custom settings, there's like 3 places in SpeedFan that have anything to do with that.

A pwm fan should respond to pwm signals, which on those fans is usually like @ 30% to 100%. If it's responding to voltage settings instead, 7vDC is @ 60%.

I haven't messed with SpeedFan in almost 7 years, the learning curve and placements of everything was just crazy. It's called SpeedFan, yet the damned thing is anything but simple. It's almost like there's no middle ground, it's either max or minimum.

 

[Insane Potatoz]

You'll probably need to dig into those fan curves custom settings, there's like 3 places in SpeedFan that have anything to do with that.

A pwm fan should respond to pwm signals, which on those fans is usually like @ 30% to 100%. If it's responding to voltage settings instead, 7vDC is @ 60%.

I haven't messed with SpeedFan in almost 7 years, the learning curve and placements of everything was just crazy. It's called SpeedFan, yet the damned thing is anything but simple. It's almost like there's no middle ground, it's either max or minimum.

Huh. How do I know if it’s responding to PWM or voltage?

 

[Karadjgne]

If the pwm wire is actually in the pwm pin now, you should be able to set in bios between pwm/auto/voltage for the headers. So if everything lines up as should according to the Dell factory wiring (yes, Dell is a pain) and the header is set for pwm, the fan should be responding to pwm signals. Same for voltage. Usually a dead giveaway will be a fan that is still responsive below @ 40% of its rpm range, DC are a minimum of 5v (out of 12v 100%)

 

[Insane Potatoz]

If the pwm wire is actually in the pwm pin now, you should be able to set in bios between pwm/auto/voltage for the headers. So if everything lines up as should according to the Dell factory wiring (yes, Dell is a pain) and the header is set for pwm, the fan should be responding to pwm signals. Same for voltage. Usually a dead giveaway will be a fan that is still responsive below @ 40% of its rpm range, DC are a minimum of 5v (out of 12v 100%)

I can’t find anything in the BIOS. what section would it be under?

 

[Insane Potatoz]

So hey sorry for coming back to this, but the problem is still there.
I'm gonna call the black yellow green blue pinout the "green pinout" and the other one the red pinout.

So the red pinout is the one used for Dell machines right? I have a fan with the red pinout but it still has this problem.
Should i try a green pinout fan? or will that damage the fan/motherboard?

 

[Insane Potatoz]

Also I tried to use the intel stock cooler on this and that seems to work fine. It just spins at around 2000 RPM and stays there. This intel cooler uses the green pinout though, so is that bad?