What air cooler to get for 3950x? I don't want water cooling.

NightReaver

Weaksauce
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103
Well.....

EKWB CPU waterblock - $110
EkWB 480mm radiator - $100
Corsair 420mm radiator - $80
EKWB RGB res - $80
EKWB Quantum Aorus GPU block w/backplate - $236
Thermaltake Riing Plus 120mm fans (x4) - $130
Thermaltake Riing Plus 140mm fans (x5) - $150
Miscellaneous fittings - $130
PETG tubing - $40-60 (I messed this up here and there.)

It can be done for less of course. But it can get expensive. It will nickel and dime you if not carefully planned.
Jesus, that waterblock. I know shopping for them might not be noob-friendly, but thank God for Barrow and Bykski for us with slimmer wallets :D
 

kamikazi

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I'm thinking now I'm narrowed down to the TT Floe Riing 360 Premium and the Corsair H150i Pro. I have a Corsair Commander in the back for control of all of my Corsair fans, so I'm leaning Corsair at this point. Plus with the TT, you have to use their special connections and their software and I'm not sure if you can manually set pump speed. You can't manually set pump speed on the Corsair in the Corsair software, have to pick a profile, but you can just plug it in to the mobo and manually control it there. However, if the TT performs better, I'll go with it. It's just hard trying to figure that out at this point looking at reviews.
 

Dan_D

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Jesus, that waterblock. I know shopping for them might not be noob-friendly, but thank God for Barrow and Bykski for us with slimmer wallets :D
The blocks for reference cards are cheaper. Those are about $160-170.
 

RavinDJ

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Cannot thank you enough guys. I don’t want to change the topic since this is an AMD PROCESSOR forum, but you guys made up my mind. I’ll go water cooling. The AIO is an all in one simple solution which makes it much easier for me. I guess water cooling was much more difficult when it first started and before it went mainstream. I’ll go with one of the better AIOs.

Now. I don’t want to change the topic from this forum, but could use recommendations in mobo and case :D
 

Mega6

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Cannot thank you enough guys. I don’t want to change the topic since this is an AMD PROCESSOR forum, but you guys made up my mind. I’ll go water cooling. The AIO is an all in one simple solution which makes it much easier for me. I guess water cooling was much more difficult when it first started and before it went mainstream. I’ll go with one of the better AIOs.

Now. I don’t want to change the topic from this forum, but could use recommendations in mobo and case :D
price range and usage?
 

Dan_D

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reasonably priced. nothing over $3000, but also not $109 or below.
Motherboards:
MSI X570 Unify
MSI MEG X570 GODLIKE
ASUS Crosshair VIII Hero
ASUS Crosshair VIII Formula

Cases:
Lian-Li PC-011 Dynamic
Lian-Li PC-011 Dynamic XL
Phanteks Enthoo Evolv
Phanteks Enthoo Evolv X
Phanteks Enthoo Elite
 

kamikazi

Gawd
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Jan 19, 2006
Messages
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Motherboards:
MSI X570 Unify
MSI MEG X570 GODLIKE
ASUS Crosshair VIII Hero
ASUS Crosshair VIII Formula

Cases:
Lian-Li PC-011 Dynamic
Lian-Li PC-011 Dynamic XL
Phanteks Enthoo Evolv
Phanteks Enthoo Evolv X
Phanteks Enthoo Elite
I've got the Asus Croshair VIII Hero in a Lian-Li PC-011 Dynamic. ;-)
Now, just trying to pick the right AIO?????
 

kamikazi

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Messages
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The Thermaltake Floe Riing 360 Premium Edition is the best AIO I've used thus far. The Corsair equivalent should be pretty good too.
Thanks, I've been getting lost in the weeds reading contradictory reviews.
 

RamonGTP

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Messages
7,895
For max air performance you're going to want some Delta fans and ear plugs.
Ahh the good ole' days. I still have my 60mm delta screamer that I used to cool my Athlon Thunderbird back in the day. No longer have the actual heat sink though. Wish I'd have kept that around as well for nostalgia.
 

kamikazi

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Messages
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Thanks, I've been getting lost in the weeds reading contradictory reviews.
I'm actually gonna take a flyer on this: https://www.amazon.com/CORSAIR-Radi...R+iCUE+H150i+RGB+PRO+XT&qid=1578339511&sr=8-1

New, looks to be the CoolIT version (as opposed to Asetek version) of the H150i Pro called the

iCUE H150i RGB PRO XT Liquid CPU Cooler $159.99

-h150i-xt-rgb-config-Gallery-H150i-RGB-PRO-XT-03.png -h150i-xt-rgb-config-Gallery-H150i-RGB-PRO-XT-05.png -h150i-xt-rgb-config-Gallery-H150i-RGB-PRO-XT-16.png -h150i-xt-rgb-config-Gallery-H150i-RGB-PRO-XT-21.png
The ML fans on this go up to 2400 rpm as opposed to 1600 rpm on the outgoing model. I only happened upon this on Amazon when I was looking at the current H150i Pro which is out of stock until February, but they have renewed versions for $100.00. I almost pulled the trigger on one of those, but glad I found this. It doesn't release until January 13th though, so my 3950x will either wait until then or limp along on the H100i Platinum SE which is also a CoolIt product. I don't really care for how you mount the CoolIt version, but I like the size of the coldplate better than the Asetek models. Here's the link to Corsair's product page: https://www.corsair.com/us/en/Categ...uid-CPU-Cooler/p/CW-9060045-WW#tab-tech-specs
 
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Mega6

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Wiring is a bit messy, not detachable but looks good.

One post and the thread is done? I was thinking the same thing.
AIO Might be fun to play wiith, but my open air case would have no problem dissipating heat off a NH-D15. I have a Phanteks heatsink on my old 3930K that is very similar. Dual cooling stack, dual fans. I get 4.4GHz out of that, it only thermal throttles with insane benchmarking 6 or 12 threads x100% cpu utilization.

Of course a 3950X is a whole different animal.
 
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Mega6

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I'm actually gonna take a flyer on this: https://www.amazon.com/CORSAIR-Radi...R+iCUE+H150i+RGB+PRO+XT&qid=1578339511&sr=8-1

New, looks to be the CoolIT version (as opposed to Asetek version) of the H150i Pro called the

iCUE H150i RGB PRO XT Liquid CPU Cooler $159.99

View attachment 213628View attachment 213634 View attachment 213636 View attachment 213638
The ML fans on this go up to 2400 rpm as opposed to 1600 rpm on the outgoing model. I only happened upon this on Amazon when I was looking at the current H150i Pro which is out of stock until February, but they have renewed versions for $100.00. I almost pulled the trigger on one of those, but glad I found this. It doesn't release until January 13th though, so my 3950x will either wait until then or limp along on the H100i Platinum SE which is also a CoolIt product. I don't really care for how you mount the CoolIt version, but I like the size of the coldplate better than the Asetek models. Here's the link to Corsair's product page: https://www.corsair.com/us/en/Categ...uid-CPU-Cooler/p/CW-9060045-WW#tab-tech-specs
video review, messy wires, hardwired - no connector. Appears to do the job, no comparison.

 

thecold

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Messages
407
Water cooling is maintenance and it's expensive. I've actually dropped the water cooling and went to a d15s.


I use that d15 on a 7940x @ 4.3 non avx, 4 avx (except 512). In case anyone is wonder that's a bit below 300 watts on p95. It's easier and requires no maintenance other than a can of air. Do I think it would limit a 3950x, probably a bit. Do I think it would limit the 3950x enough for me to warrant going to water cooling, probably not.

I'm using a 7940x not using water, heat is literally limiting me 300-400 MHz and I could just pull the water cooling out of my closet.
 

kamikazi

Gawd
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Messages
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video review, messy wires, hardwired - no connector. Appears to do the job, no comparison.

This is for the old Asetek H150i Pro. The one I linked above is the new Cool It H150I Pro XT which doesn't release until next week.
 

TheSlySyl

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Messages
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I have a slightly older, but extremely similar cooler in my system. The Thermalright Macho Rev B. My CPU maxes at around 70c, but its not quite at the heat load of a 3950x, but i'm sure it can handle that no problem. Given that 3950Xs, for some reason, tend to run cooler than 3900Xs - I'm sure that it, or the Noctua DH-15S, or the Dark Rock Pro 4, will suffice.
There's also a newer Macho Rev C.
https://www.amazon.com/Macho-Rev-C-rev/dp/B07S5VHRXM
 

kirbyrj

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Messages
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I'm actually gonna take a flyer on this: https://www.amazon.com/CORSAIR-Radi...R+iCUE+H150i+RGB+PRO+XT&qid=1578339511&sr=8-1

New, looks to be the CoolIT version (as opposed to Asetek version) of the H150i Pro called the

iCUE H150i RGB PRO XT Liquid CPU Cooler $159.99

View attachment 213628View attachment 213634 View attachment 213636 View attachment 213638
The ML fans on this go up to 2400 rpm as opposed to 1600 rpm on the outgoing model. I only happened upon this on Amazon when I was looking at the current H150i Pro which is out of stock until February, but they have renewed versions for $100.00. I almost pulled the trigger on one of those, but glad I found this. It doesn't release until January 13th though, so my 3950x will either wait until then or limp along on the H100i Platinum SE which is also a CoolIt product. I don't really care for how you mount the CoolIt version, but I like the size of the coldplate better than the Asetek models. Here's the link to Corsair's product page: https://www.corsair.com/us/en/Categ...uid-CPU-Cooler/p/CW-9060045-WW#tab-tech-specs
I had the newish H100x which was a CoolIT product just with the crappy cheap fans on my 3900x until I swapped it out for a 360mm AIO. It worked pretty well for the price (I think it was sub-$70AR). I would definitely give this one a try with the better fans and larger radiator. I didn't like the mounting mechanism either. Uses the stock clips on either side and it's harder to get good mounting pressure IMO vs. a four corners type of mount, but I never had any issues with the temps.
 

Jamie Marsala

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I have a 3900X and had the Noctua NH-D15S with a second fan mounted to it and I can tell you that it ran damn hot and was throttling when at %100 load. Running Prime95 it would easily hit 95 degrees and sit there, where my AIO does not hit 95 degrees after a 30 minute load on the standard test, blend. So take that as you will. Sure for everyday facebook posting I am sure an air cooler will be just fine, but I assume no one buys a 3950x for just surfing the net.
 

Dan_D

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Do I think it would limit a 3950x, probably a bit. Do I think it would limit the 3950x enough for me to warrant going to water cooling, probably not.
I'm going to disagree with that. Maybe it wouldn't justify full on water cooling, but with an air cooler you are leaving performance on the table. I don't understand why you would with a $750 CPU.
 
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bobzdar

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I'm running a corsair h100i platinum AIO on my 3950X and it does not struggle at all. Temps top out at 62C in all core benchmarks like cinebench, maximum I've seen is 65C under cpu-z stress test. Normal use in photogrammetry, which is what I bought it for, is like 60C with all cores loaded and gpu loaded 100%. 360mm is massive overkill. Custom loops is overkill. High end air should work fine.
 

Dan_D

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360mm is massive overkill. Custom loops is overkill. High end air should work fine.
Ludicrous, untrue, and unsubstantiated nonsense in that order. And I'll prove it.

Before the days of boost clocks, a CPU's clock speed was a set value from the factory. If you had a Pentium 200MHz processor, then you could easily measure the cooling solution by your CPU temps and that's all you needed to do. When loaded, the CPU's clocks were a fixed value. Even when overclocking, older CPU's still had a fixed maximum clock speed and once your cooling could no longer extend the clocks, you were at a point where you could determine which cooling solutions were good enough or could be considered overkill. These days, clock speeds are dynamic. A CPU no longer has a set clock speed value. Instead, you are given a base clock as a minimum standard of what you can expect under load. Then, you are given a boost clock value which is what the CPU can achieve under certain ideal conditions. There are no guarantees you'll ever see these clock speed values nor are there stipulations on how long the CPU will hold that value or even any guarantees on precise conditions which will result in a given clock speed. We do know how to trigger these conditions for test purposes but there are a lot of variables here and what you get varies by individual configuration and even by specific CPU.

Your CPU's boost clock behavior is determined by a number of factors. EDC, PPT, and TDC. They are electrical design current, power package tracking and thermal design current. One additional factor is CPU temperature. If you hit the limits, it will drop the clocks to a lower range to reduce not just temperatures, but in order to keep EDC, PPT and TDC within a certain operational range. It is important to note that the EDC, PPT and TDC values are set by AMD at the factory for these CPU's. There are stock values and precision boost 2 values. The latter obviously are more generous and allow the CPU to reach higher clocks conditions permitting. Precision Boost Overdrive overrides these values and uses motherboard manufacturer specified values.

upload_2020-1-7_12-41-6.png


On my test bench right now, at default settings, the 3950X test chip operates in similar temperature ranges. I'm seeing temperatures around 55-58c. I'm getting 3.95-4.0GHz clock speeds running Cinebench or other multithreaded workloads. EDC is at 97%, TDC and PPT are at 100%. These are limits defined by AMD. This isn't PB2, or PBO mind you. These values are more conservative keeping the PPT, EDC and TDC as my limiting factors. As a result, temperature isn't a limitation here. Therefore, my CPU's clocks are limited by those values I keep mentioning. AMD's stock values are conservative and it allows the CPU to operate on virtually any motherboard and with a modest cooling solution. These values keep the temps down and like this, yes, a 240mm AIO would suffice. That said, the CPU is capable of more than the above. So in this scenario we are leaving performance on the table and not getting the most out of our 3950X.

upload_2020-1-7_12-20-4.png


Using PB2, higher values are allowed for TDC, EDC and PPT. Using custom water, I'm at 76.11c or thereabouts, but my clock speeds have now reached 4.12GHz to 4.15GHz running Cinebench. If that's what I'm getting on custom water, your 240mm AIO would be out of headroom. Your temps would likely be in the 85c range or worse. Is that doable? Maybe, but I'm not sure that your clocks would actually be as high running that cooler. They certainly aren't running high end air cooling as others in this thread have mentioned. Some have mentioned getting only around 3.9GHz on high end air cooling. These clock speed differences might not seem like much, but Zen 2 scales very well with clock speed increases. Unfortunately, the architecture doesn't have much headroom left in it, which is why we aren't seeing clocks that look more like Intel's. We know from looking at single threaded applications and confirming boost clocks that these micro bursts into the 4.4-4.7GHz range allow the Ryzen 3000 series to be more competitive and even faster than Intel in some cases. Keep in mind, that single-threaded performance is where Intel still does quite well.

upload_2020-1-7_12-31-21.png


Under Precision Boost Overdrive, or PBO, we see some differences in performance. Our clocks are actually slightly lower and the CPU temperatures are essentially the same. Thus, our limitations are something else. This has always been the case with the upper end Ryzen 3000 series CPU's. What it seems like is that the clocks are held longer, even if they are a bit lower. This doesn't always result in a boost in performance either and as such PB2 is generally the better option over the supposedly more aggressive PBO which worked well on second generation CPU's like the Ryzen Threadripper 2920X.

upload_2020-1-7_12-33-28.png


Now, we are on full manual control. Our voltage is locked in and our CPU clocks are set to 4.3GHz. All the cores are set the same and I repeated the Cinebench R20 run. This was taken near the end of the run, so the temps are at their highest. I will say that I've seen worse temps on this configuration, but it's cooler today than it was the other day when I tested this. But, as you can see the slight increase in clock speeds has resulted in a slight increase in temperatures. Running all core overclocks on these things produces much higher than normal temperatures. It's not usually worth doing and while temps do play a part in our limitations here, simply not seeing high temperatures doesn't mean that your cooling is adequate. It might be adequate without PB2 or PBO running. Or, it could mean that other limitations are in place keeping your clocks down so you aren't seeing your thermal limitations.

I don't have a high end air cooler on hand or I'd have tested it. But based on the data I've seen and shared here, there is virtually no chance that you aren't leaving at least some performance on the table by opting for air cooling instead of a high end 360mm AIO at the very least. Custom water cooling will produce better results. Given the cost of building a good water cooling setup, I can see why some people would be hesitant to go that route despite spending $750 on a CPU. A good setup is going to be at least $400-$500 and it does require more maintenance to deal with and more skill to put it together. First timers will waste more money than they need to by not accounting for every fitting, length of tubing, or flat cutting tubing wrong or whatever. They might need a different case or have to buy some tools to get the job done.

All that said, I stand by my assertion that high end air cooling isn't enough to tame a 3950X and get the most out of it. I think I've shown enough data to prove it as well. Furthermore, if your really feeling up to it, let's try an experiment: If you really think your cooling solution is up to the task, try a 4.3GHz manual overclock on all cores and run Blender bench or Gooseberry and then tell me what your temperatures are. As you can see, at 4.3GHz all core I'm at 79c on custom water cooling doing a quick Cinebench run. I'm using a Koolance Exos 2.5 (360mm radiator) and an Alphacool Eisblock water block. This specific test represents both a heavily multithreaded workload and it represents the edge of what these chips can typically do with a manual all core overclock. If your cooling solution can handle 4.3GHz all core doing something like Prime95, Blender, Gooseberry, etc. then its probably good enough.

I'm just using Cinebench here. This is quick and dirty. When you load up something like Gooseberry, you'll quickly see your cooling solutions limitations. Using this, I'll hit 85c by the end of the hour long run at a 4.3GHz all core overclock. Doing that, you'll likely overrun a 240mm AIO and an air cooler would have NO chance of getting through the test.

Again, AMD doesn't recommend air cooling for the 3950X and doesn't include one with it. Looking at the temps, clocks and real world power consumption, its easy to see why.
 

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Dark12

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Wiring is a bit messy, not detachable but looks good.



AIO Might be fun to play wiith, but my open air case would have no problem dissipating heat off a NH-D15. I have a Phanteks heatsink on my old 3930K that is very similar. Dual cooling stack, dual fans. I get 4.4GHz out of that, it only thermal throttles with insane benchmarking 6 or 12 threads x100% cpu utilization.

Of course a 3950X is a whole different animal.
Not really. 3950 is only 20 more than 3930
 

Furious_Styles

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Woah I think Dan just crit the thread with the monster post! Someone should step up and see how the D15 does in comparison. I don't have a 3950 otherwise I would.
 

RavinDJ

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AMD Ryzen 9 3950X 16-core, 32-thread Unlocked Desktop Processor ordered.
MSI MEG X570 GODLIKE Motherboard ordered.
Lian Li O11 Dynamic XL (White) Full Tower Gaming Computer Case ordered.
CORSAIR iCUE H150i RGB PRO XT, 360mm Radiator Liquid CPU Cooler ordered.

All I need now is DDR4 memory and an M.2 SSD and a PSU.

I cannot thank you enough guys. This is my first build since a very, very, very, very long time ago. It will last me a looooooong time.
 

thecold

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AMD Ryzen 9 3950X 16-core, 32-thread Unlocked Desktop Processor ordered.
MSI MEG X570 GODLIKE Motherboard ordered.
Lian Li O11 Dynamic XL (White) Full Tower Gaming Computer Case ordered.
CORSAIR iCUE H150i RGB PRO XT, 360mm Radiator Liquid CPU Cooler ordered.

All I need now is DDR4 memory and an M.2 SSD and a PSU.

I cannot thank you enough guys. This is my first build since a very, very, very, very long time ago. It will last me a looooooong time.
Enjoy! :)
 

kamikazi

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I'm running a corsair h100i platinum AIO on my 3950X and it does not struggle at all. Temps top out at 62C in all core benchmarks like cinebench, maximum I've seen is 65C under cpu-z stress test. Normal use in photogrammetry, which is what I bought it for, is like 60C with all cores loaded and gpu loaded 100%. 360mm is massive overkill. Custom loops is overkill. High end air should work fine.
Your H100i sounds too good to be true. What are your ambient temps and what app are you using to measure temps? Even in CB20 when I watch temps hovering in the low to mid 60s, there always seems to be a bump up to the mid 70s on the max temp reading that I never see happen in real time. I'm using HWINFO 64.
 

bobzdar

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Ludicrous, untrue, and unsubstantiated nonsense in that order. And I'll prove it.
OP did not indicate any oc or pbo. I'm not running either. A 240mm aio is perfectly adequate for a stock 3950X. Nothing you posted refutes that.

Now pressing a 3950X for all its worth? Of course, you will need a lot of cooling and I wouldn't do it on air or aio. But that's not what op is asking. Moving to 360mm custom water for 100-150mhz isn't worth it to me, but understand it is for those that want to really push it.
 
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bobzdar

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Your H100i sounds too good to be true. What are your ambient temps and what app are you using to measure temps? Even in CB20 when I watch temps hovering in the low to mid 60s, there always seems to be a bump up to the mid 70s on the max temp reading that I never see happen in real time. I'm using HWINFO 64.
I'm using hwinfo64 as well, ambient is ~20C in the house but typical case temp is 30C and the fan curve is set to maintain 35C coolant temps, so starts ramping above 30% fan speed at 30C, 100% fan at 35C. Pump is set to extreme. Coolant peaks at 34C with fans at 90% under sustained all core load, so there's still a little headroom left. I don't ever see temp spikes, but I do see them on my 3700X on air. It's installed in an sff so not unexpected. It sounds like you're getting similar performance except for the temp spikes, not sure what would cause that, though I know there were some agesa revisions that people saw that behavior.
 

bobzdar

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On my test bench right now, at default settings, the 3950X test chip operates in similar temperature ranges. I'm seeing temperatures around 55-58c. I'm getting 3.95-4.0GHz clock speeds running Cinebench or other multithreaded workloads. EDC is at 97%, TDC and PPT are at 100%. These are limits defined by AMD. This isn't PB2, or PBO mind you. These values are more conservative keeping the PPT, EDC and TDC as my limiting factors. As a result, temperature isn't a limitation here. Therefore, my CPU's clocks are limited by those values I keep mentioning. AMD's stock values are conservative and it allows the CPU to operate on virtually any motherboard and with a modest cooling solution. These values keep the temps down and like this, yes, a 240mm AIO would suffice. That said, the CPU is capable of more than the above. So in this scenario we are leaving performance on the table and not getting the most out of our 3950X.

View attachment 213892

Using PB2, higher values are allowed for TDC, EDC and PPT. Using custom water, I'm at 76.11c or thereabouts, but my clock speeds have now reached 4.12GHz to 4.15GHz running Cinebench. If that's what I'm getting on custom water, your 240mm AIO would be out of headroom. Your temps would likely be in the 85c range or worse. Is that doable? Maybe, but I'm not sure that your clocks would actually be as high running that cooler. They certainly aren't running high end air cooling as others in this thread have mentioned. Some have mentioned getting only around 3.9GHz on high end air cooling. These clock speed differences might not seem like much, but Zen 2 scales very well with clock speed increases. Unfortunately, the architecture doesn't have much headroom left in it, which is why we aren't seeing clocks that look more like Intel's. We know from looking at single threaded applications and confirming boost clocks that these micro bursts into the 4.4-4.7GHz range allow the Ryzen 3000 series to be more competitive and even faster than Intel in some cases. Keep in mind, that single-threaded performance is where Intel still does quite well.

View attachment 213894

Under Precision Boost Overdrive, or PBO, we see some differences in performance. Our clocks are actually slightly lower and the CPU temperatures are essentially the same. Thus, our limitations are something else. This has always been the case with the upper end Ryzen 3000 series CPU's. What it seems like is that the clocks are held longer, even if they are a bit lower. This doesn't always result in a boost in performance either and as such PB2 is generally the better option over the supposedly more aggressive PBO which worked well on second generation CPU's like the Ryzen Threadripper 2920X.
My understanding, based on amds talks, is that precision boost 2 (pb2) is the stock boost behavior with stock tdc,edc,ppt and scalar values. It allows boosting within those limits based on load in a linear fashion (ie more cores loaded boost would gradually drop), as opposed to precision boost (1) which was just on 1st gen ryzen and only had 2 levels of boost - single core and 2+ core. The ability to increase those tdc,edc,ppt and scalar values is precision boost overdrive (as you're over driving the precision boost limits), not pb2 itself, and is considered overclocking, technically voiding warranty (nbd). The PBO option in bios usually auto sets the board limits for those values with 1x scalar. The performance enhancer in asus boards sets the scalar as well, which starts to affect silicon reliability. That preset pbo function appears mostly broken for 3rd gen, you have to set the values manually.
 

Dan_D

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My understanding, based on amds talks, is that precision boost 2 (pb2) is the stock boost behavior with stock tdc,edc,ppt and scalar values. It allows boosting within those limits based on load in a linear fashion (ie more cores loaded boost would gradually drop), as opposed to precision boost (1) which was just on 1st gen ryzen and only had 2 levels of boost - single core and 2+ core. The ability to increase those tdc,edc,ppt and scalar values is precision boost overdrive (as you're over driving the precision boost limits), not pb2 itself, and is considered overclocking, technically voiding warranty (nbd). The PBO option in bios usually auto sets the board limits for those values with 1x scalar. The performance enhancer in asus boards sets the scalar as well, which starts to affect silicon reliability. That preset pbo function appears mostly broken for 3rd gen, you have to set the values manually.
You are correct. For whatever reason I often have to go into AMD Ryzen Master and tell it to use PB2 or it doesn't work properly. This likely comes down to some specific BIOS implementations if I had to guess the reason. Basically, this is what I saw on the MSI MEG X570 GODLIKE in this instance. That's why I had a more or less "stock" value. But you are correct, PB2 is supposed to be the stock behavior. PBO values are defined by the motherboard, which seems to be roughly the same as AMD's. You can go in and change them yourself, but I've never seen this impact the results in any meaningful way.
 

kamikazi

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I'm using hwinfo64 as well, ambient is ~20C in the house but typical case temp is 30C and the fan curve is set to maintain 35C coolant temps, so starts ramping above 30% fan speed at 30C, 100% fan at 35C. Pump is set to extreme. Coolant peaks at 34C with fans at 90% under sustained all core load, so there's still a little headroom left. I don't ever see temp spikes, but I do see them on my 3700X on air. It's installed in an sff so not unexpected. It sounds like you're getting similar performance except for the temp spikes, not sure what would cause that, though I know there were some agesa revisions that people saw that behavior.
I haven't ever tried setting fan curves based on coolant temp. The cpu temp would be way too high if I did. Maybe I'll look at it again. Right now, I have pretty aggressive curves based on core temp, but the 3950x only boosts to around 3900 MHz in CB20.
 
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