Heatsinks apparently offer a perk over using an AIO

arknor

arknor

arknor

Caporegime
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apparently grounding CPU heatsink has always been a thing?

I found this post from all the way back in 2005
according to the poster AMD had a white paper saying it reduces EMI by -4db, but since the post is so old the white papers link is dead.
apparently it turns the heatsink into an EMI shield

www.head-fi.org

Reduced my PC's EMI emissions : What Great Sound Quality....

This has to be the best tweak i have ever done. After following AMDs suggestions on reducing EMI(from a pdf whitepaper),I did the following. 1) Connected a Wire between the heatsink fins and Ground.That is ground of t he power connectors. AMD says this reduces EMI by 4db!! 2)Connected a...
www.head-fi.org www.head-fi.org

Googles AI even backs up the claim

Grounding a CPU heatsink helps to reduce emissions and ensure that the heatsink shields the integrated circuit (IC) from high-frequency (HF). Here are some reasons why grounding a heatsink is important:


  • Reduces radiated EMI
    Grounding the heatsink returns common-mode displacement current to the reference plane, which reduces radiated EMI.


  • Prevents the heatsink from acting as an antenna
    If left floating, a heatsink can act like a large dipole antenna and radiate strongly.


  • Reduces voltage difference
    Grounding the heatsink to the printed circuit board (PCB) ground-reference-plane (GRP) reduces the voltage difference between the heatsink and the ground reference plane.
Some ways to ground a heatsink include:
  • Using a heatsink with a conductive finish
  • Using a smaller grounded heatsink
  • Using a grounded thermal washer between the heatsink and the component
A heat sink is a component that absorbs and disperses heat generated by electronic components. It's typically made of a thermally conductive material, such as aluminum or copper.
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How come I've never heard of anyone doing it?

further investigation even reveals the gas lifts in office chairs have been known to output enough EMI to make a monitor blink

Display intermittently blanking, flickering or losing video signal – DisplayLink Support

support.displaylink.com support.displaylink.com

Surprisingly, we have also seen this issue connected to gas lift office chairs. When people stand or sit on gas lift chairs, they can generate an EMI spike which is picked up on the video cables, causing a loss of sync. If you have users complaining about displays randomly flickering it could actually be connected to people sitting on gas lift chairs. Again swapping video cables, especially for ones with magnetic ferrite ring on the cable, can eliminate this problem. There is even a white paper about this issue.
Click to expand...

So why aren't we all wiring our heatsinks to the case or ground pin on the mobo? :D
 
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Even with a window, etc. the case itself should protect from most external noise albeit some don't have much metal aside from the motherboard tray. Most internal sources of noise probably already reduced in impact by common mode rejection where appropriate.
 
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Nathlm said:
I don't know how much stock I put in this, seems very much like those "audiophile hdmi cables"
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AMD did a study on it though and google claims the science holes up, grounding a heatsink creates an emi shield blocking/protecting the cpu from interference.


to ground it all you would need to do it attach a cable from a metal part of the heatsink directly to a screw in the case.

the whole case should be grounded anyway
 
arknor said:
Googles AI even backs up the claim

Grounding a CPU heatsink helps to reduce emissions and ensure that the heatsink shields the integrated circuit (IC) from high-frequency (HF). Here are some reasons why grounding a heatsink is important:


Reduces radiated EMI
Grounding the heatsink returns common-mode displacement current to the reference plane, which reduces radiated EMI.


Prevents the heatsink from acting as an antenna
If left floating, a heatsink can act like a large dipole antenna and radiate strongly.


Reduces voltage difference
Grounding the heatsink to the printed circuit board (PCB) ground-reference-plane (GRP) reduces the voltage difference between the heatsink and the ground reference plane.

Some ways to ground a heatsink include:

Using a heatsink with a conductive finish
Using a smaller grounded heatsink
Using a grounded thermal washer between the heatsink and the component

A heat sink is a component that absorbs and disperses heat generated by electronic components. It's typically made of a thermally conductive material, such as aluminum or copper.
Click to expand...
Click to expand...

Eww

Prompting a robot to regurgitate scraped up words in a hopeful mess and presenting it as a source.
 
Grounding cooler won't hurt, but I seriously doubt any of us would ever find any differences.

White paper authors are like research papers. Authors want notoriety and skew their reports to fit their hypothesis.
 
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arknor said:
AMD did a study on it though and google claims the science holes up, grounding a heatsink creates an emi shield blocking/protecting the cpu from interference.


to ground it all you would need to do it attach a cable from a metal part of the heatsink directly to a screw in the case.

the whole case should be grounded anyway
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Yeah, but I don't think it'd actually be useful, is what I'm saying

Just like how pure gold is an amazing conductor, but it's not going to help your hdmi cable, nor is it practical
 
2005 eh? So about the same time frame as overclocking a CPU by drawing on it with a pencil. I have little doubt components were noisy as all hell then because of the lack of shielding, because they didn't need to be shielded as heavily because they weren't as vulnerable to interference.

2 decades later and you can't so much as cough too close to a PCI-E Gen 5 controller without screwing up its signalling. Everything today is significantly shielded because everything today is incredibly sensitive to interference.

I doubt you'd have seen any real-world benefit from grounding a tower cooler in 2005, certainly you'd see zero today. But still, slapping a grounding cable on a cooler and charging an extra 50 bucks for it sounds like the perfect upsell gimmick, no doubt aimed at the sort of people who buy gold-plated optical cables and AM5 contact frames.
 
<Computer generated nonsense paragraphs>
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This regurgitation is about heatsinks in electronic circuits, not general computing/digital silicon. Guess what, the vast majority of heatsinks are cooling power supply transistors or analog signal amplifiers. An audio amplifier has very different noise/shielding requirements than a multi-GHz CPU.

Heatsinks apparently offer a perk over using an AIO
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You can ground the cold plate of a CPU block as easily as you can ground a metal heatsink. Both equally effective/equally pointless.
 
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