Question 9900K : Noctua D15 vs 240mm AIO advice

hornetmax

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Hi all, my current setup is:

  • Case: Fractal Meshify C
  • i9 9900K on Gigabyte z390 Gaming SLI
  • 4x 8GB Corsair Vengeance LPX 3000 C15
  • CPU cooling: Thermalright Macho Rev.B with its 1400mm TY-147 fan
  • Case cooling: 2x Noctua 140mm P14s 1700 front intake, 1x Corsair 140mm AF140 top-rear exhaust, 1x Fractal 120mm X2 GP rear exhaust
  • Nvidia RTX 3070, stock
With the 9900K stock, during intensive AVX loads (h265 enc, Prime95 Small AVX) the CPU temps and VRMs were too high for my taste: roughly, both were hitting 100C.
So I crippled the 9900K a bit (PL1 150W / auto time, and PL2 200W / 2secs ) and lowered both CPU max temps and VRM temps: roughly, 80C and 90C max, respectively.

Question 1: if I wanted to swap my CPU cooler (Thermalright Macho RevB), what would be better in terms of both CPU temps and VRM temps:
  1. Noctua D15
  2. A 240mm AIO, like a Liquid Freezer II 240 mounted as top exhaust (I can't go bigger than 240 on top in my Meshify C)
I was kind of expecting the AIO to be better for the VRMs (as it evacuates the CPU heat), but reading around I seem to find that this is not straightforward.
Opinions ?

Questions 2: I also plan to replace may rear and top-rear exhaust fans with decent ones.
Top-rear (if I don't go AIO) -> Noctua NF-P14 redux 1700
Rear -> Any advice between the 3 Noctuas NF-S12B redux-1200 PWM, NF-P12 redux-1300 PWM and NF-P12 redux-1700 PWM ?


Thanks in advance !
 
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Aeacus

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Question 1: if I wanted to swap my CPU cooler (Thermalright Macho RevB), what would be better in terms of both CPU temps and VRM temps:
  1. Noctua D15
  2. A 240mm AIO, like a Liquid Freezer II 240 mounted as top exhaust (I can't go bigger than 240 on top in my Meshify C)
I was kind of expecting the AIO to be better for the VRMs (as it evacuates the CPU heat), but reading around I seem to find that this is not straightforward.
Opinions ?
Here's one good article for you to read, where king of air coolers (Noctua NH-D15) was put against 5x high-end AIOs, including former king of AIOs (NZXT x61 Kraken),
link: http://www.relaxedtech.com/reviews/noctua/nh-d15-versus-closed-loop-liquid-coolers/1

This should answer your question.

Questions 2: I also plan to replace may rear and top-rear exhaust fans with decent ones.
Top-rear (if I don't go AIO) -> Noctua NF-P14 redux 1700
Rear -> Any advice between the 3 Noctuas NF-S12B redux-1200 PWM, NF-P12 redux-1300 PWM and NF-P12 redux-1700 PWM ?

NF-P12 redux-1700 PWM would be the best of the three, in terms of performance (airflow and static pressure).
 

boju

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Im running 11700k, default turbo, with d15. Ibt max 83c. Games will never run that high nor should prime with avx be practical imitating a warm day, not that high without some ac. Aio alone without additional strategically placed fans won't have all that much air pulled through and around cpu so air is going up and above over vrms. Unless you had fans drawing from psu chamber straight up or lowest bottom at front, vrms would missing quite a bit of air flow.
 

hornetmax

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Here's one good article for you to read, where king of air coolers (Noctua NH-D15) was put against 5x high-end AIOs, including former king of AIOs (NZXT x61 Kraken),
link: http://www.relaxedtech.com/reviews/noctua/nh-d15-versus-closed-loop-liquid-coolers/1

This should answer your question.
Thanks, but not really. It tells me that, roughly speaking, the D15 and a good 240mm AIO are more or less on par for CPU temps & noise, but it tells me nothing about the impact of each on VRM temps.
 

Phaaze88

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Question 1: if I wanted to swap my CPU cooler (Thermalright Macho RevB), what would be better in terms of both CPU temps and VRM temps:
  1. Noctua D15
  2. A 240mm AIO, like a Liquid Freezer II 240 mounted as top exhaust (I can't go bigger than 240 on top in my Meshify C)
I was kind of expecting the AIO to be better for the VRMs (as it evacuates the CPU heat), but reading around I seem to find that this is not straightforward.
Opinions ?
You only need to look at the "VRM Fan Benchmark vs. MOSFET Thermals" section at 10:18.

It's quite possible for neither cooler to best the other in both. As old as it is, the D15 is still used in comparisons due to how well balanced it is. Thermalright's Peerless Assassin kinda spanks it, if it's available to you.
The D15 bests some 240mm due to the higher rpm ranges on the latter, and when noise normalized to a user's comfort zone, the fans on some AIOs have lost enough air pressure to fall into 2nd place. Not saying that the D15 can't be too audible, mind you.

The 240mm limit in the roof of cases sucks. In the front, sure. IMO, ideally, if one is going to top mount an AIO, bigger is better - 280mm or greater.
240mm just don't offer enough over a decent air cooler, except in a case where the latter wouldn't fit, or one is lacking case fans(IMO, again).

Questions 2: I also plan to replace may rear and top-rear exhaust fans with decent ones.
Top-rear (if I don't go AIO) -> Noctua NF-P14 redux 1700
Rear -> Any advice between the 3 Noctuas NF-S12B redux-1200 PWM, NF-P12 redux-1300 PWM and NF-P12 redux-1700 PWM ?
/scratches head
After adjusting fan curves to your comfort zone, I have to wonder just how much of an improvement would even be noticed...
 

hornetmax

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You only need to look at the "VRM Fan Benchmark vs. MOSFET Thermals" section at 10:18.
Damn, I watched that some time ago and focused on the AIO with/without the VRM fan results without realising it was also comparing VRM temps with the D15. So OK, that seals it for me: that 280 AIO isn't doing significantly better than the D15 on the VRMs, so the same AIO in 240 format does probably the same or worse. Never liked AIOs anyway :p Thanks !

It's quite possible for neither cooler to best the other in both. As old as it is, the D15 is still used in comparisons due to how well balanced it is. Thermalright's Peerless Assassin kinda spanks it, if it's available to you.
Spanks the D15 once you factor in the prices of the two (D15 vs Peerless Assassin) or spanks it overall ?
I've read that not even the Thermalright Frost Commander really spanks the D15 overall (i.e. price not a factor).

/scratches head
After adjusting fan curves to your comfort zone, I have to wonder just how much of an improvement would even be noticed...
You mean between the 3 120mm Noctua fans or between my current fans and the suggested "upgrade to Noctuas" ?
 

Phaaze88

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Spanks the D15 once you factor in the prices of the two (D15 vs Peerless Assassin) or spanks it overall ?
I've read that not even the Thermalright Frost Commander really spanks the D15 overall (i.e. price not a factor).
The price. They come close to what the D15 can do for about half the price or more.
A problem I've noticed is that Thermalright's support is lacking in some regions. If I wanted to purchase Thermalright case fans or get replacement cpu cooler fans in the US, I'd be in trouble, as they're not widely available here.

You mean between the 3 120mm Noctua fans or between my current fans and the suggested "upgrade to Noctuas" ?
The rear and top-rear you were considering replacing. The specs you see for fans only apply at 100% rpm. Below that is an unknown, as fan performance doesn't scale linearly.
So who's to say that the new fans will be better, if at all(except at 100% rpm)?
 

hornetmax

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Yeah, I've seen that review of the AK620, but to be honest, there are very different results depending where you look.
I do know that GN is kind of an authority (and I don't dispute that) but still, others serious outlets still put the D15 ahead of the AK620 or Peerless Assassin (in terms of performance only, of course, if you factor the price inm then it's a no brainer).

What's funny is that in that same review, they say that if you find the AK620 at 90$, then it's a no-go as there are 240 AIOs (e.g. EK AIO 240) for close to that price that are "better". Looks like and endless game: we just said 240 AIO not worth vs a D15, but here we have the AK620 that is somehow "better" than the D15 (incl. price) but then if AK620 price is 90$ (which is probably still less than a D15) they do advise to go AIO ...
 

hornetmax

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The AK620 is going for $65 these days, and the DH15 is $100.
That's understood. But if you forget about price, it's not clear what's better.
Most say D15 is a bit ahead, some say it's kind of equal, some says AK620 is a bit better.

As said, if price is a factor then one should even consider something cheaper: where I live the prices for D14, AK620 and Peerless Assassin SE are respectively 110E, 70E and 42E ...
 

Phaaze88

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Most say D15 is a bit ahead, some say it's kind of equal, some says AK620 is a bit better.
That's because a cooler does better/worse on one platform compared to the other, due to factors such as:
-how the IHS bends under heat cycles, concave/convex
-cooler cold plates are slightly concave/convex
-the location and size of the hotspots on the die(s)

Only TechPowerUp is doing both Intel and AMD cooler tests. They didn't start doing this until April 2021.
Here's a couple samples:
Doing better on the AMD test system than their Intel one.

Faring better on Intel instead.

You may have noticed the NH-D15 and AK620 on those lists. On AMD, they're pretty neck and neck between the Blender and AIDA FPU only tests.
On Intel, it's a similar scenario, until the overclocked tests came into play, which the AK620 falls behind.
 
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hornetmax

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You may have noticed the NH-D15 and AK620 on those lists. On AMD, they're pretty neck and neck between the Blender and AIDA FPU only tests.
On Intel, it's a similar scenario, until the overclocked tests came into play, which the AK620 falls behind.
Agree. AK620 very on par with D15 on AMD but a bit behind on Intel in case of OC. Also, D15 quieter at full fan speed.
So to me, the D15 is better performance-wise (especially for Intel).
However, AK620 is more compact and, of course, quite a lot cheaper.

Final note: I don't know if the difference is really in AMD vs Intel. If I read TPU methodology correctly, the AMD CPU used was roughly 105/150W (noOC/OC) while the Intel one was 125/200W (noOC/OC).
So it could just point out that the gap between D15 and AK620 widens as power goes up (more than an AMD vs intel thing).

Thanks a lot !
 
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Phaaze88

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Agree. AK620 very on par with D15 on AMD but a bit behind on Intel in case of OC. Also, D15 quieter at full fan speed.
So to me, the D15 is better performance-wise (especially for Intel).
However, AK620 is more compact and, of course, quite a lot cheaper.

Final note: I don't know if the difference is really in AMD vs Intel. If I read TPU methodology correctly, the AMD CPU used was roughly 105/150W (noOC/OC) while the Intel one was 125/200W (noOC/OC).
So it could just point out that the gap between D15 and AK620 widens as power goes up (more than an AMD vs intel thing).

Thanks a lot !
Yes, power consumption is another factor alongside the other points. Apologies for leaving it out.
 

hornetmax

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I've ordered my D15 and while waiting I added a 2nd Corsair AF140 as top exhaust (I forgot I had a spare one sitting in a drawer): it help ed the VRM temps a lot !!

A quick 4min OCCT Power test (SSE only) before/after adding the 2nd AF140 shows:
  • the CPU temp raising more slowly but still hitting thermal limits: that's OK as my Macho revB is not enough for a 9900K with MCE on.
  • the VRM temps at the end of the 4min are 82C vs 98C ! After the 4min they weren't really steady state, but extrapolating/eyeballing I'd say that the 2nd AF140 hare shaved off anything between 10C and 15C (maybe even more).
I'll slot the D15 in, swap my cheapo rear fan (Fractal X2 GP-12) for a Noctua NF-S12B redux-1200 PWM and call it a day.

Thanks all !