Question Any ideas on how I can either use USB or an unused CPU2 power header to power fans with external PWM?

[Cyber_Akuma]

I added some custom side-fans to a prebuilt workstation for better cooling, they were powered by a SATA cable that has an option to plug it into a fan header for PWN control (the fan headers are all proprietary and more or less maxed out on current by the also proprietary fans, so I could not just power them from that). I had built a custom setup that pulled the PWN signal from one of the existing proprietary fan pins and fed it into said SATA cable. This one:

https://www.amazon.com/gp/product/B093ST9W5L

This worked for about a month, then my HDD suddenly disconnected (No that's not my OS drive, it's just for storage). After some testing I found out that if I have the fans plugged into the same SATA power cable as the HDD, it stops the HDD from being recognized anymore. So now I am trying to figure out an alternate way to power the fans while also still getting a PWN signal to them.

Option one is to use an unused CPU2 power header on the PSU, from my understanding it simply has +12V and ground pins. The port on the very right here:

https://imgur.com/D2V02tw

View: https://i.imgur.com/D2V02tw.jpg


Though I am not sure how safe it would be to pull power for fans from that considering the CPU1 connector is obviously supplying power to my CPU, if that could somehow mess up the power on CPU1 (assuming they are even connected) and cause my system to become unstable.

Option two is to use an internal USB port. It's a port intended to plug a flashdrive into to run an OS from as an alternate to a SATA or NVME drive, but it should be more than enough to provide power for three small fans (Though I have a USB power tester on the way just to be safe). Issue with this is that USB is 5 volts, and PC fans run on 12 volts. Sure, there are cables with a 5V to 12V step-up converter like this:

https://www.amazon.com/dp/B07QFG6LFR/

But they don't provide a way to control PWM other than manually through a dial.

This is what the fans look like with the existing SATA adapter:

https://imgur.com/ANbBjhU

View: https://i.imgur.com/ANbBjhU.jpeg


And them connected to SATA power and the external PWM wire I am pulling from the headers:

https://imgur.com/X4QJgRV

View: https://i.imgur.com/X4QJgRV.jpeg


Is there any way I can wire up either that CPU2 or USB header to the fans while also pulling the PWN signal externally? I am thinking it would likely be safer and easier to go the USB route and that's the route I want to go. but I am not sure how I would combine the power from that USB cable and the PWM signal from another source together like that, are there any types of cables that would let me do that? The only ones I could find expect to pull both power and PWN from the same standard fan header as a source, none that let you take the PWM signal from a separate source like that SATA cable lets you.

System Specs:
Dell Precision T5810
OS: Windows 10
CPU: Xeon E5-2667 V4
RAM: 4x32GB DDR3 2400MHz ECC
GPU: EVGA RTX 2060 Super
PSU: Dell FT7T6 825W

 

[Ralston18]

This part: "I am thinking it would likely be safer and easier". [My Bold.]

What is safer and easier is to read and follow all of the relevant component documentation; user guides/manuals, etc..

Do not "combine" or othewise connect devices etc. that are not specifically and explicitly supported by the manufacturers - individually and collectively.

Although there are standards there are also proprietary connections that could cause electricity to go where it should not go or with the wrong currents and voltages.

Some mismatch could end badly.

= = = =

The posted objective being to add cooling fans - correct?

What temperature problems, if any, exist?

Update your post to include full system hardware specs and OS information.

Add more details regarding specific temperature related problems or concerns.

 

[Cyber_Akuma]

The posted objective being to add cooling fans - correct?

What temperature problems, if any, exist?

Update your post to include full system hardware specs and OS information.

Add more details regarding specific temperature related problems or concerns.

Add fans with PWM control, yes.

The GPU was overheating

Dell Precision T5810
OS: Windows 10
CPU: Xeon E5-2667 V4
RAM: 4x32GB DDR3 2400MHz ECC
GPU: EVGA RTX 2060 Super
PSU: Dell FT7T6 825W

 

[Ralston18]

Has the GPU always been overheating or is that something that just started happening?

Basically looking at the case, the interior layout, and the current existing fans I am wondering about the existing airflow directions, etc..

No fans on top?

More fans (with or without PWM control) may not help.

Hopefully some other members will take a closer look at it all and post accordingly.

Expect some questions about the airflow directions and rates.

Not an immediate answer; however, best to not risk anything until there is more certainty about the reason(s) the GPU is overheating and viable solutions - fans or otherwise...

 

[Cyber_Akuma]

Has the GPU always been overheating or is that something that just started happening?

Basically looking at the case, the interior layout, and the current existing fans I am wondering about the existing airflow directions, etc..

No fans on top?

More fans (with or without PWM control) may not help.

Hopefully some other members will take a closer look at it all and post accordingly.

Expect some questions about the airflow directions and rates.

Not an immediate answer; however, best to not risk anything until there is more certainty about the reason(s) the GPU is overheating and viable solutions - fans or otherwise...

Yes, though I only got the GPU for it recently, but since the day I got it I tested it and it was hitting over 80C.

The airflow is pretty much nonexistent. The case just has three very high CFW fans that each use almost a full amp in the front and depend on trying to force air through the entire case (other than the single fan the CPU cooler has). I also added a rear fan because heat kept building up behind the CPU cooler and it was ridiculous that there was no exhaust fan there. Thankfully the CPU fan was much lower than one amp so I could safely connect two fans to that header.

I ran literally dozens of tests with various configurations with and without the fans using OCCT's power stress test, the fans made a big difference. The GPU was hitting the mid-80s, with the fans it was in the high 60s.

https://imgur.com/EgNEDZJ

View: https://i.imgur.com/EgNEDZJ.png

 

[Ralston18]

The screenshot images are too small for me to read.

Overall though (going out of my comfort zone here - full disclosure) I would be wary of trying to work around or otherwise adding more fans, controllers, etc..

If the case/system cannot be cooled down just on its' own merits then you may need to reconsider the current build and case configuration.

That said, focus on finding some configuration that at least can reduce and hold the temperature(s) down.

In the meantime, others may offer more specific suggestions.

 

[Cyber_Akuma]

Unfortunately since it's a prebuilt with many components of it being proprietary I don't have much options of a different build or case, and I can't afford to build an entirely new PC, I have to try to make do with this.

This fan configuration was considerably keeping the temperature down until for some reason it suddenly prevented my HDD from working when plugged in together, which is why I am trying to find an alternate way to power them.