My Fan is Running with PC Unplugged

CaptainK42

Prominent
Apr 13, 2017
5
0
510
0
So here's a strange one. I turned my PC off last night and even unplugged it, but the CPU fan and LED stayed on regardless. It only stopped once I unplugged the HDMI cable from the back of my graphics card (my monitor was on). Any ideas on what that is or if it represents a failing component?

Thanks!
Kirk
 
Sep 4, 2018
18
0
20
4
Captain,

I dont see this happening with an HDMI cable. (Could be wrong)

I see this issue happening with a Display Port Cable. Some DP cables have what is called a PIN 20 connected inside the cable which actually allows some power to pass through the GPU and have enough juice to keep a fan/led lights on. When you unplug the cable everything goes dark.

You might need to buy a higher quality HDMI cable or if your using a DP cable find one that is certified. I had the same issue.
 
Sep 4, 2018
18
0
20
4
Captain,

I dont see this happening with an HDMI cable. (Could be wrong)

I see this issue happening with a Display Port Cable. Some DP cables have what is called a PIN 20 connected inside the cable which actually allows some power to pass through the GPU and have enough juice to keep a fan/led lights on. When you unplug the cable everything goes dark.

You might need to buy a higher quality HDMI cable or if your using a DP cable find one that is certified. I had the same issue.
 

TJ Hooker

Illustrious
Herald

A graphics card would have to be explicitly designed to take advantage of the power available on that DP pin, and I'd be pretty surprised if that was the case. Also, that pin is only rated for 1.5 W, which would probably be pretty tight for LED + fans. Have you actually seen any graphics card that does this?
 
Sep 4, 2018
18
0
20
4



Yes...Mine.

EVGA 1070 SC. The fan will still spin very slowly and the LED lights are very dim. When i bought a certified DP cable. I never had the issue again.
 
Sep 4, 2018
18
0
20
4
@TJ Hooker

My GPU light/fans were completely off.

My rear Exhaust fan was still spinning and the LED lights of the fan were on but very dim.

Now, when I rebuilt my computer and I was still using that old DP cable. I added the corsair H100i Water block and the block light would remain dimly lit. It drove me nutts!

And yes even if the power supply was completely unplugged! Its crazy!

It took about 3 hours to find a certified DP cable that didnt have PIN 20 Connected inside the cable.
 
Sep 17, 2019
1
0
10
0
Captain,

I dont see this happening with an HDMI cable. (Could be wrong)

I see this issue happening with a Display Port Cable. Some DP cables have what is called a PIN 20 connected inside the cable which actually allows some power to pass through the GPU and have enough juice to keep a fan/led lights on. When you unplug the cable everything goes dark.

You might need to buy a higher quality HDMI cable or if your using a DP cable find one that is certified. I had the same issue.
Thank you!,

i registered to this site just so i could thank you.
My PSU was making a humming sound and the fan was spinning really slowly even when i unplugged the PC completely.
Was about to call the exorcist.
unplugging the DP-cable from an older model screen did the trick.
No more humming. No more demons occupying my computer.
Praise the lord!

Sam
 

ASK THE COMMUNITY

TRENDING THREADS