AIR vs AIO. 18c drop in temps

I thought it was the Pro lol. Would be useful to see temps on a Noctua NH-D15.

So, as to this, Prime AVX will push one of my cores above 90C on a 8600k @5Ghz 1.34v. I offset 1 AVX to keep it under 90C. This is on a Noctua NH-D15S, expected or to hot? I've reseated it twice using Noctua's included thermal paste. Airflow is not a problem with full NZXT Phantom that I have custom modded with 2 200mm Phanteks, 120mm+140mm

When I say custom modded I removed the HDD bay allowing for better airflow.

If you're not de-lidded, adding more cooling will have diminishing returns as most of the heat is trapped between the ihs and die and not being directly transferred to the IHS. De-lidding will net you a ton of temp savings. Way more than any air/aio/loop.
 
Here's the exact problem with that review and if you read it, they even kinda mention it but excuse it:

"We've been battling the question whether or not to actually use a Core i7 4790K on a Z97 motherboard. The Haswell processors all have poor heat transfer from the silicon die to the IHS."

So the reviewer is fully aware that most of the heat issues are between the IHS and Die meaning that coolers are only doing surface heat transfers *BUT* the reviewers doesn't state that will greatly limit cooling performance which should have been the next step.

This is not the reviewers fault but we're now comparing a 4c/8t thread that has much better thermal density than Coffee Lake Refresh. You can watch more on thermal density here: https://www.youtube.com/watch?v=uLVzRY27A-I&t=1046s

I ended up buying a dark rock 4 back when I built my PC by relying on poorly formulated reviews and being knowledge limited as I hadn't been tracking PC trends since Sandy Bridge days. It's ultimately my decision to buy it so I take full responsibility but I'm glad to have moved past it. For the record, I had the same AIO before and it died within 30mins. So all is not rosy on the AIO front either.

If you want to look at good reviews for coolers, look at their methodology. That's way more important than the results page.


You guys must be right, its been ages since I built a PC just I recently read tons of reviews before on the DR pro4 and its pretty clear its one of the best air coolers going review wise, many reviewers pitch it in the same league as the Noctua NH-D15s and similar offerings.

Even in the review linked above:

https://www.eteknix.com/alphacool-eisbaer-lt-360-cpu-liquid-cooler-review/4/

The Noctua NH-D15 which is meant to be similar to DRpro 4 is a good 4-7c less @ load then the alpha cool.

Yes the reviews are tricky and not always right.
 
I thought it was the Pro lol. Would be useful to see temps on a Noctua NH-D15.

So, as to this, Prime AVX will push one of my cores above 90C on a 8600k @5Ghz 1.34v. I offset 1 AVX to keep it under 90C. This is on a Noctua NH-D15S, expected or to hot? I've reseated it twice using Noctua's included thermal paste. Airflow is not a problem with full NZXT Phantom that I have custom modded with 2 200mm Phanteks, 120mm+140mm

When I say custom modded I removed the HDD bay allowing for better airflow.
Prime AVX will push any cooler to those temps if the CPU is overclocked so I am sure that is normal. My [email protected] and 1.2V will get to around 88C on an NH-D15S under Prime 95 AVX within minutes. Other stress tests like Realbench run in the mid to late 60s C.
 
If you're not de-lidded, adding more cooling will have diminishing returns as most of the heat is trapped between the ihs and die and not being directly transferred to the IHS. De-lidding will net you a ton of temp savings. Way more than any air/aio/loop.

Prime AVX will push any cooler to those temps if the CPU is overclocked so I am sure that is normal. My [email protected] and 1.2V will get to around 88C on an NH-D15S under Prime 95 AVX within minutes. Other stress tests like Realbench run in the mid to late 60s C.

Robert & Itron thanks.

Think we had this convo in another post Robert. I've actually found someone reputable who does it for £14.99 using thermal grizzly liquid metal with warranty within 30 minutes driving distance. Established Ebay delidder, guess I got lucky that he's a stone throw away from me. So I can buy the kit or just pay pennies to have it done with a warranty. When I say warranty, he replaces if it goes wrong, cant't ask for more than that. Might pay just to do it with him so I'm confident to do it if it needs redoing in the future.

Itron, pretty much the same here. At least now I can rule out everything else and focus on delidding. Think for now I'm just going to run 4.8Ghz to avoid running an offset. Noticed that a lot of programs & games must run some type of AVX as my clock was pretty much at 4.9 doing these tasks so might as well just drop some voltage. Only really hit 5Ghz in say non AVX prime anyhow.
 
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I know this batted around a lot so I figured I'd share my findings. The results are below and everything is exactly the same in bios. The air cooler was cleaned. All fans are 100% I use realbench not because of some magic reason. Only because I knew I could run it just shy of throttling the CPU on air.

Settings:
9900k
HT OFF
5.2ghz
1.305v in bios
z390 aorus pro
Turbo LLC
46x core
Case = haf x with side panel off
Interesting data, but what is your case fan setup with each setup? Was air cooler getting air the same temp as radiator is? Below link is basic guide to airflow and optimizing case airflow by monitoring airflow temp into coolers. You might find it of intereest.
https://forums.overclockers.co.uk/t...-i-put-my-temp-sensor.18564223/#post-26159770
 
Interesting data, but what is your case fan setup with each setup? Was air cooler getting air the same temp as radiator is? Below link is basic guide to airflow and optimizing case airflow by monitoring airflow temp into coolers. You might find it of intereest.
https://forums.overclockers.co.uk/t...-i-put-my-temp-sensor.18564223/#post-26159770

It's a haf x with the side panel removed. Rear exhaust fan and had a table fan blowing cooler air on the DR4 to avoid throttling. Without the fan, it'd throttle or crash out.

AIO had no fan assitance. Mounted top with top exhaust and what was the rear exhaust fan got flipped to rear intake to provide some air flow over the vrm's.

Ambient temps for both were within 1 degree in the same location.
 
It's a haf x with the side panel removed. Rear exhaust fan and had a table fan blowing cooler air on the DR4 to avoid throttling. Without the fan, it'd throttle or crash out.

AIO had no fan assitance. Mounted top with top exhaust and what was the rear exhaust fan got flipped to rear intake to provide some air flow over the vrm's.

Ambient temps for both were within 1 degree in the same location.
No fan assistance? You mean no fans on radiator?

How did you measure the temp of air into each to determine they were within 1c?
 
To show how the temps scale with voltage on the AIO, here is a 1 hr run of real bench with the same settings as OP EXCEPT:
- vcore is now 1.35v in bios
- Multiplier 53x

fujOi3o.png

As I stated earlier, it's easy to even max out this AIO on a 9900k. Same settings as op except:
- HT ON
- Core 52x
- 1.35v is bios
*note the massive jump in CPU power package and a corresponding drop in vr vout minimum. We went from 118amps to 152amps thus the massive jump in heat. This is on the same voltage in bios! As a reference cinebench in the non HT setup above is around 180w"

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A few things to note about cooling a 9900k. The good news is that with HT on, you'll never have to worry about too much vcore as you'll always be thermally throttled. Direct die can shave about 10c. After that you get into oversized and multiplier radiators, chillers, dry ice and LN2.

My particular chip hits a voltage wall between 5.3 and 5.4 with HT off. What does that means? The jump above you see going from 5.2 to 5.3 with HT off was 0.45v. However, going to 1.42v and 5.4ghz which is a .70v jump is barely stable booting into windows, never mind running a decent benchmark. All in all, my sweet spot is 5.3ghz. I also can't cool the chip at 1.42v/5.4ghz even with AIO on max.

If your biggest system stress is gaming, you can use use realbench as your test suite. I'd recommend finding the lowest voltage it'll run stable at then add .020v as a buffer to cover random scenarios. 1hr test should be ideal. If you're going do a lot of number crunching and scientific modeling, you need to use P95 as your baseline. It's more stressful so you'll need to raise your vcore or drop multiplier compared to realbench. If you're doing rendering, download blender benchmark and run the long test which takes about an hour.

Hopefully the info above helps those with more thermally limited chips such as the 9700k/9900k and the upcoming 9900ks.
 
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https://www.youtube.com/watch?v=gAy9uNnFr0I&app=desktop


Good video of high end air coolers dealing with an average oc of a 9900k.

I always recommend Noctua coolers, owning the NH-D15S myself. Glad to see that my recommendations are valid!

Still, those temps @5ghz were hot! Curious to see if Noctua can respond and release a fan capable of some serious cooling on the newer chips considering its likely to get worse.
 
Noctua are good coolers, but they are also £10-30 more than others with similar performance and noise levels. TRUE Spirit 140 Power is about 50 quid, has good mountinng system, cools as well (maybe a little better and is as quiet as NH-D15S (75 quid) and NH-D15 (85 quid).
 
You have to run the AIO for longer than 15 minutes to provide a fair comparison, I'd recommend an hour for it to reach its maximum temp. The air cooler will reach its maximum temp within a few minutes, see this video:

I've tried this and it only runs about 2 or 3c hotter after 15 minutes than it does after 15 seconds
 
Comparing the OP's AIO to his air cooler is not exactly fair as someone said its not exactly high end.

In all good reviews it shows that the best of the high end air Coolers (Noctua D15 etc) are as good or better than AOI's esp for performance to noise ratio, custom water is another story though as obvious it going to be cooler.
 
Comparing the OP's AIO to his air cooler is not exactly fair as someone said its not exactly high end.

In all good reviews it shows that the best of the high end air Coolers (Noctua D15 etc) are as good or better than AOI's esp for performance to noise ratio, custom water is another story though as obvious it going to be cooler

As i linked this video above
https://www.youtube.com/watch?v=gAy9uNnFr0I&app=desktop You can see how a D15 (and other high end air coolers) perform understress.

Here's a 15min run using his settings on the alphacool. 12-13c difference is a lot. If I could drop my temps by that much, I could run 53x daily.

The settings I copied:
50/43x
1.33v bios
15min loop of R20. File, preferences, minimum time duration = 900seconds

UeAvgmA.png

On an overclocked 9900k, a good AIO (swiftech, alphacool, ek) is a notable step above air coolers. I plan to do similar testing when I go custom and direct die as I want to have another 10-12c off my temps.
 
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In all good reviews it shows that the best of the high end air Coolers (Noctua D15 etc) are as good or better than AOI's esp for performance to noise ratio, custom water is another story though as obvious it going to be cooler.

Except for decent AIO's from water cooling companies the likes of Alphacool and EK. IMO, are the AIOs to go for, not your run-of-the-mill Asetek jobs.
 
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