Noctua NH-D15 Club

doyll · Feb 8, 2020

I hope I am wrong and we have a new Noctua out sooner. But I'm not very optimistic.

Aenra · Feb 8, 2020

Can't blame you.. The only good thing out of all this is that with so many revisions and iterations one can ..with moderation.. hope for a good product eventually, lol

Unrelated to this thread, but am also wondering *** happened with their TRX coolers; they were announced well in advance, showcased, and then, nothing. It's an important window to lose, as they only release once a year and whomever needed a TR4/X cooler already has one by now. So best case scenario is sometime near end of next year (next -and last within the 'Zen' arc- TRX launch).

* Jeesus almighty, the site now censors W-T-F? Just how much more are we to culturally backtrack for the sake of post-millennial offendotrons?

umeng2002 · Feb 9, 2020

Does anyone know or can measure the height difference between the white AM3 and down spacers compared to the grey AM4 spacers?

I'm trying to increase the mounting pressure on my AM4 system.

Aenra · Feb 9, 2020

umeng2002 said:
Does anyone know or can measure the height difference between the white AM3 and down spacers compared to the grey AM4 spacers?

I'm trying to increase the mounting pressure on my AM4 system.

If that's all you want, why over-complicate?
Get some good quality, sturdy plastic round washers and voila; though it does need be said that by default, it's more than adequate, ergo if you really do have mounting issues, they're 100% unrelated to the total newtons applied to the IHS.
Your toys, your responsibility.
(and if you insist pressure is what's lacking and that it isn't your fault, washers are all you need)

umeng2002 · Feb 9, 2020

I'm thinking it's mounting pressure, because my thermals are the same whether the fans are at 900 rpm or max.

doyll · Feb 9, 2020

umeng2002 said:
I'm thinking it's mounting pressure, because my thermals are the same whether the fans are at 900 rpm or max.

What is your TIM print like? Maybe you are using too much TIM? We what as much metal to metal contact as possible with TIM only filling tiny voids in and between surfaces. We do not want a layer of TIM between them.

Aenra · Feb 9, 2020

umeng2002 said:
I'm thinking it's mounting pressure, because my thermals are the same whether the fans are at 900 rpm or max.

That's not the D15's mounting mechanism applying insufficient mounting pressure; i'll be frank and say it outright, i don't even know how you reached that conclusion, given all the variables you'd have had to exclude to reach it.. but it's not that.
With a right mounting, the D15 applies close to 500 Newtons of force on that IHS. Says everything that needs to be said in regard to that.

Unmount (and i mean unmount, backplate too), clean both, check your fans, their cabling, whatever's driving them, check your paste, remount/re-apply paste.

GeneO · Feb 10, 2020

Aenra said:
That's not the D15's mounting mechanism applying insufficient mounting pressure; i'll be frank and say it outright, i don't even know how you reached that conclusion, given all the variables you'd have had to exclude to reach it.. but it's not that.
With a right mounting, the D15 applies close to 500 Newtons of force on that IHS. Says everything that needs to be said in regard to that.

Unmount (and i mean unmount, backplate too), clean both, check your fans, their cabling, whatever's driving them, check your paste, remount/re-apply paste.

I would add that because of this, it is also not a problem of too much TIM. Any excess will get squeezed out by the pressure. Putting too little TIM would be more likely.

doyll · Feb 10, 2020

GeneO said:
I would add that because of this, it is also not a problem of too much TIM. Any excess will get squeezed out by the pressure. Putting too little TIM would be more likely.

I dissagree.

While it depends on may variables including TIM density / consistency and mounting pressure, too much TIM will not spread / be pushed out from between IHS and cooler base. Years ago Hardware secrets did testing with 5 different amounts of TIM and found less was better. Of course TIM print has to cover area of IHS that has CPU chip under it. Link below is their results.
https://www.overclock.net/forum/22335323-post10.html
You can see they found 3c of difference, and their TIM was not a very high density / thick in consistancy either.

As I said before, key to a good seat and heat transfer is direct metal to metal contact with TIM only filling microscopic voids in surfaces. We do not want a layer of of TIM because TIM does not transfer heat near as well as metal.

Normal TIM is rated 3.5-12.5W/m K
Liquid Metal TIM is . 32-50W/m K
Copper is rated at . 400W/m K
Air is only rated . . 0.024W/m K

So you can see while TIM is a many times better than air, it's still 8-114 times worse than copper .. in other words if our mount ends up with a layer of TIM between IHS and CPU over CPU die heat transfer is going to be very poor.

Also keep in mind the IHS on our CPUs is not really a heat spreader. It's too thin to spread heat more than maybe a mm. What it really does is spread the mounting load of cooler to it's edges which are outside of the area of the 1000+ contacts between CPU and motherboard. This is so the area with all these contacts does not flex and damage them.

This is why I determine how big and where CPU die is under IHS and use a dob in middle of it that spreads to a TIM print that covers all of CPU die.

As for the 500 newtons thing, the definition of newton is "A newton is a unit of force that will accelerate one kilogrqam of mass one meter per second squared. Just as meters measure distance, newtons measure force." One newton = 0.00014503773800722psi, so 500 newton would only be 0.72psi. So either my definition of newton is wrong or there is much more than 500 newton of force involved here.

GeneO · Feb 10, 2020

doyll said:
I dissagree.

While it depends on may variables including TIM density / consistency and mounting pressure, too much TIM will not spread / be pushed out from between IHS and cooler base. Years ago Hardware secrets did testing with 5 different amounts of TIM and found less was better. Of course TIM print has to cover area of IHS that has CPU chip under it. Link below is their results.
https://www.overclock.net/forum/22335323-post10.html
You can see they found 3c of difference, and their TIM was not a very high density / thick in consistancy either.

As I said before, key to a good seat and heat transfer is direct metal to metal contact with TIM only filling microscopic voids in surfaces. We do not want a layer of of TIM because TIM does not transfer heat near as well as metal.
Normal TIM is rated 3.5-12.5W/m K
Liquid Metal TIM is . 32-50W/m K
Copper is rated at . 400W/m K
Air is only rated . . 0.024W/m K

So you can see while TIM is a many times better than air, it's still 8-114 times worse than copper .. in other words if our mount ends up with a layer of TIM between IHS and CPU over CPU die heat transfer is going to be very poor.

Also keep in mind the IHS on our CPUs is not really a heat spreader. It's too thin to spread heat more than maybe a mm. What it really does is spread the mounting load of cooler to it's edges which are outside of the area of the 1000+ contacts between CPU and motherboard. This is so the area with all these contacts does not flex and damage them.

This is why I determine how big and where CPU die is under IHS and use a dob in middle of it that spreads to a TIM print that covers all of CPU die.

As for the 500 newtons thing, the definition of newton is "A newton is a unit of force that will accelerate one kilogrqam of mass one meter per second squared. Just as meters measure distance, newtons measure force." One newton = 0.00014503773800722psi, so 500 newton would only be 0.72psi. So either my definition of newton is wrong or there is much more than 500 newton of force involved here.

no, way off. pressure = force/unit area. So a chip of 38mmx38mm = .00144 square meter. Pressure in Pascal for 500N applied across the chip = 500N/.00144 m**2 = 347,143 PA. Converted to psi = 50 psi.

However, I don't know where that 500N of force comes from. The only reference I could find was a site that measured the force on an NH-D15 to be 270N, which would be equivalent of about 27 psi,

doyll · Feb 10, 2020

GeneO said:
no, way off. pressure = force/unit area. So a chip of 38mmx38mm = .00144 square meter. Pressure in Pascal for 500N applied across the chip = 500N/.00144 m**2 = 347,143 PA. Converted to psi = 50 psi.

However, I don't know where that 500N of force comes from. The only reference I could find was a site that measured the force on an NH-D15 to be 270N, which would be equivalent of about 27 psi,

Assuming you missed it in post #1927 .. a couple of posts before your last one.

Aenra said:
....
With a right mounting, the D15 applies close to 500 Newtons of force on that IHS. Says everything that needs to be said in regard to that.
.....

Are you saying my quote of definition of Newton is incorrect or my math is incorrect?

My point really has nothing to do with Newtons of force calculation, but with the fact the pressure our cooler mounting kits apply (you say 27PSI) may not enough to force all of a large amount of stiff/thick TIM between IHS and cooler base out so we end up with metal to metal contact with TIM only filling microscopic voids.

If OP is using some thick / stiff TIM it could easily end up creating a layer between IHS and cooler base and seriously lower heat transfer from IHS to cooler base.

I've tried to find CPU chip specs published by AMD or Intel about what mounting pressure should be and couldn't find any. If anyone finds them please post links so we can seel. :thumb:

GeneO · Feb 10, 2020

doyll said:
Assuming you missed it in post #1927 .. a couple of posts before your last one.

Are you saying my quote of definition of Newton is incorrect or my math is incorrect?

My point really has nothing to do with Newtons of force, but with the fact the pressure our cooler mounting kits apply is not enough to force all TIM between IHS and cooler base out so we end up with metal to metal contact with TIM only filling microscopic voids.

If OP is using some thick / stiff TIM it could easily end up creating a layer between IHS and cooler base and seriously lower heat transfer from IHS to cooler base.

I've tried to find CPU chip specs published by AMD or Intel about what mounting pressure should be and couldn't find any. If anyone finds them please post links so we can seel. :thumb:

No I meant the actual source of that 500N. Just because someone says it doesn't make it true. Noctua apparently does not publish this information, and I found one site that saifd they measured 270N, but they didn't say how they measured that.

Your definition and math are both incorrect. You are right in your definition of unit of force, but incorrect in how you interpret it as a pressure - Newton is a unit of force not pressure ans you are mising them up. Pressure is force per unit area. So the pressure from 500N spread uniformly over the area of the chip = 500N / area of chip (in square meters) = pressure in units Pascal. You have to divide by the area.

50 psi will squeeze most TIM out fine, like thermal grizzly, Noctua paste etc. I use to follow the "thinnest is best" so used a size of a grain of rice or less. I get better results using a bit more now. I agree there is a limit and you don't want a lot of paste oozing out either.

EDIT: I did find one review that said the Noctua spring mounting system limits the force to 50 lbf (force pounds) which corresponds to 222N or ~ 22 PSI, Maybe they got that from Noctua

8051 · Feb 10, 2020

Wouldn't the vibration of a fan(s) that is transferred to the IHS-heatsink have a tendency to pump out TIM?

Aenra · Feb 10, 2020

doyll said:
Are you saying my quote of definition of Newton is incorrect or my math is incorrect?

No, i'm saying that a correctly mounted D15 applies more than enough pressure; so much so that one:
i) does NOT need modifications to increase it further.
ii) does NOT need to give a crap about how much paste they apply; they could drown the mobo in paste if they wanted. Once the D15's correctly mounted, excess will leave on its own. That's sufficient force for you.
iii) does NOT need to worry about "vibrations" from the fan affecting the IHS, paste or backplate, no.. we're talking a lot of pressure here.

Rule of thumb guys, don't over-complicate unless: i) you need to, ii) you're certain you grasp what you're talking about. Not being offensive, am just being, well, literal i guess.
You canot draw conclusions when you lack the basics. I think that's a logical thing to say.

(and to doyll again in specific) All of which i've already typed, so not sure why repeating any of this would help. The rest is.. just you... and although i could given your follow up posts, i'm not going to start an argument with you either; you're free to accept or disregard

umeng2002 · Feb 10, 2020

I'm using MX-4. I've mounted it twice. Used the spread method. I was thinking there is some weird variation in my mobo causing the mounting hardware not to function correctly.

Using prime95, thermals will go to mid 70s when it hits 75, the mobo automatically turns the fans to 100%, yet the CPU doesn't cool down. It just stays around 75 to 77.

Aenra · Feb 10, 2020

@8051 since you mentioned it (unfortunately as it may confuse things further, lol), vibrations are a 'no'. Resonance however is possible, but that is a different phenomenon altogether, it has to do with amplification and oscillation (because it needs a certain frequency, doesn't always get to happen); it lastly has nothing to do with 'force' as the other poster meant it, but rather with the material's actual composition/chemical structure itself. And even so, you can't have resonance down there.
Some people confuse the two, some people confuse either or both with "coil whine", which is yet a different, third, thing.

Until you (in plural) have read enough to grasp more than the basics, stick to the facts as we know them empirically. Or, start a new thread so that we don't get to cover the same stuff every odd post.
Again, no offense meant

Aenra · Feb 10, 2020

umeng2002 said:
I'm using MX-4. I've mounted it twice. Used the spread method. I was thinking there is some weird variation in my mobo causing the mounting hardware not to function correctly.

Using prime95, thermals will go to mid 70s when it hits 75, the mobo automatically turns the fans to 100%, yet the CPU doesn't cool down. It just stays around 75 to 77.

Man you've been here since 2010.. you still don't know how to do this?

I don't know if you're talking about the CPU in your sig or another; i don't know which and how many fans you're using; i don't know if your mobo drives them correctly (always an issue); i don't know your ambients; i don't know if your paste is ten years old; i don't know "Prime", i know FTTs, i know large and small, i know ranges for thermals and ranges for power and you're not saying which; i don't know why for the love of God you'd test something like that with the fan revolutions changing, automatically at that.. you need them set to something stable; i don't know about your airflow; i don't know about the backplate itself, maybe you've stripped a thread; there's so much i don't know.

But the procedure is covered in advance and then some. Do stuff in the right order, then post something more concrete 'cause right now? Who knows honestly?

GeneO · Feb 10, 2020

Aenra said:
No, i'm saying that a correctly mounted D15 applies more than enough pressure; so much so that one:
i) does NOT need modifications to increase it further.
ii) does NOT need to give a crap about how much paste they apply; they could drown the mobo in paste if they wanted. Once the D15's correctly mounted, excess will leave on its own. That's sufficient force for you.
iii) does NOT need to worry about "vibrations" from the fan affecting the IHS, paste or backplate, no.. we're talking a lot of pressure here.

Rule of thumb guys, don't over-complicate unless: i) you need to, ii) you're certain you grasp what you're talking about. Not being offensive, am just being, well, literal i guess.
You canot draw conclusions when you lack the basics. I think that's a logical thing to say.

(and to doyll again in specific) All of which i've already typed, so not sure why repeating any of this would help. The rest is.. just you... and although i could given your follow up posts, i'm not going to start an argument with you either; you're free to accept or disregard

Not being offensive either, but I am certain I grasp what I am talking about and believe me I certainly do not lack the basics. Where did you get the 500N figure from and what do you think it means when you say "this is plenty enough force"? Can you actually put that into a context of what amount of force is good or bad? Force does not have much relevance when talking about the interface between the IHS and cooler. Pressure does.

Aenra · Feb 10, 2020

GeneO said:
Force does not have much relevance when talking about the interface between the IHS and cooler. Pressure does.

Not offended , not at all

If anything, i'm the one that usually gets to offend folks, lol, due to how i express myself.. though not the intention, i do tend to..

When talking Newtons, we're talking force; applied. There is nothing unrelated between newtons the unit, and force, as the [W]ork applied.
Second law of motion derived, classical mechanics. I'm talking just fine.

Now how others talk, and whether they mean what i -think- they mean or not.. that's a different page and not in my book. I cannot know how they write their own book.
Ergo, again, may we please stick to the basics?

umeng2002 · Feb 10, 2020

Aenra said:
Man you've been here since 2010.. you still don't know how to do this?
I don't know if you're talking about the CPU in your sig or another; i don't know which and how many fans you're using; i don't know if your mobo drives them correctly (always an issue); i don't know your ambients; i don't know if your paste is ten years old; i don't know "Prime", i know FTTs, i know large and small, i know ranges for thermals and ranges for power and you're not saying which; i don't know why for the love of God you'd test something like that with the fan revolutions changing, automatically at that.. you need them set to something stable; i don't know about your airflow; i don't know about the backplate itself, maybe you've stripped a thread; there's so much i don't know.

But the procedure is covered in advance and then some. Do stuff in the right order, then post something more concrete 'cause right now? Who knows honestly?

What are you on about? I know I know more than almost anyone on this board about testing and thermodynamics. I've tested it in all the proper ways. What I don't know is the height of the of the grey stand offs since I don't feel like taking the cooler off again right now to measure.

I don't live in a 3rd world country so assume I live in a house with air conditioning. That means my ambient is in the low 70°s F.

If there was some significant information, I'd mention it... like small FFTs being a degree hotter than smallest FFTs in Prime95... which it isn't significant, so I didn't mention it.

As I said, higher fan speeds aren't helping the cooler, since I know what I'm doing, I tested it with the case open and fans at constant speeds as well as my custom fan curve. Given that, other than a broken or overwhelmed heat pipe, mounting pressure might cause that behavior. I am expecting the cooler to scale better with increased airflow than it is.

Noctua NH-D15 Club

doyll

Aenra

umeng2002

Aenra

umeng2002

doyll

Aenra

GeneO

doyll

GeneO

doyll

GeneO

8051

Aenra

umeng2002

Aenra

Aenra

GeneO

Aenra

umeng2002

Top Contributors this Month

Recommended Communities