Question Why does TDP and PPT differ, on consumer CPUs? And what role does Core Performance Boost and Turbo Clocks have on TDP and wattage?

VirtualLarry

No Lifer
Aug 25, 2001
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Serious question. I've got a 65W-rated TDP Ryzen R5 1600, in a rig, on a 65W-rated AMD stock heatsink. It's blue-screening, crashing, and the CPU temps just keep going up and up.

I updated HWMonitor, and it's showing a "Package Power" for the entire chip, at 82W or so. No wonder it's constantly overheating and crashing. 82W TDP CPU > 65W TDP Heatsink.

The worst part is, this is AFTER limiting the number of PrimeGrid threads, down from 12 to 9. That's right, I'm not even running the CPU at a full thread load.

Edit: Yes, I know that the obvious answer, is to "get a better heatsink", and that the "stock heatsink" for the 1600 was the 95W TDP model. Which, at the time, was stated that AMD wanted to give users the ability to OC on the stock heatsink. Now I know that was a lie, it's because AMD CPUs (at least, the 1600), are NOT able to stay within their stated rated specs.

Edit: A slight update, very important, actually. My original premise for this thread, was that I *thought* I was using a 65W TDP-rated AMD stock Wraith Stealth cooler with my Ryzen R5 1600 CPU, and it was crashing, at "stock BIOS" settings, which includes "Core Performance Boost" on "Auto", which defaults to enabled, to allow "Turbo Clocks" (the 1600 has an ACT of 3.4Ghz). I was initially placing the blame on AMD for the fact that HWMonitor reported the "Package Power" as something like 82W, which I thought was overcoming the 65W-rated heatsink. As it turned out, I actually was using a 95W Wraith Stealth (copper-cored) in the first place. Yet, it was still crashing due to overheating of the CPU. Part of this was due to the heat load of dual GPUs mining, and part of it was due to using a case that had NO vents on top, no fan mounts, no rad mounts, nothing but a solid steel top, and only a single 120mm exhaust out the rear, combined with the fact that my PCs are in desk cubbies. They are open to the front, and have dual 120mm intakes and vented fronts, but that still wasn't enough to prevent the CPUs from slowly creeping up in temp, passing 95C, and crashing/restarting.

Thus far, I have split the two GPUs up, one per PC (same case, same type cubby, same EVGA 650W G1+ 80Plus Gold PSUs), and disabled CPB on both of them (one has a 3600 CPU, one has a 1600 CPU), and then also in Wattman, set the Power Limit for the RX 5600XT (which was a refurb, both of them) to -20%. Thus far, overnight, they seem to have stabilized at under 90C on the CPU, and haven't crashed.
 
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uzzi38

Platinum Member
Oct 16, 2019
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Well, the thing is by their definition they do run within their rated specs. All of AMD's 65W desktop CPUs are designed to hold 88W under long term load. All of their 95W CPUs are designed for 132W under long term load, and their 105W CPUs do 114W. There's a GN article that explains AMD's TDP definition, but for the most part, you're best off ignoring it because it's extremely convoluted and instead looking for the PPT (power pulled form the socket) definition.
 

NostaSeronx

Diamond Member
Sep 18, 2011
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If PPT can't be kept at a temperature for a certain amount of time it should throttle down to TDP.

PPT Zone 2: 75 degrees C for x amount of time.
PPT Zone 1: 85 degrees C for y amount of time.
TDP Zone 0: 95 degrees C for z amount of time.
Throttle Zone -1: 105 degrees C for a amount of time.

See if you can observe this behavior:
two cores @ 3.7 & four cores @ 3.4 => Effectively PPT Zone2
two cores @ 3.6 & four cores @ 3.4 => Effectively PPT Zone2
six cores @ 3.4 => TDP below certain temperature, Effectively PPT Zone1
six cores @ 3.2 => TDP above certain temperature, TDP Zone 0

If you see:
six cores @ <1.4 GHz => Effective throttle zone has been tripped.

Overall, Excavator onwards should not crash from thermals unless overclocked by user. They aren't lying about TDP, it just that AMD offers pre-enabled non-warranty killing overclocks.
 
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VirtualLarry

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Aug 25, 2001
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Overall, Excavator onwards should not crash from thermals unless overclocked by user.
LOL! You post some really funny off-the-wall s**t Nosta, but that one takes the cake.

I'm of the belief (with significant, nearly three years now of first-hand experience with Ryzen 6C/12T CPUs), that if you plan to put a "serious load" on a Ryzen CPU, you NEED to water-cool it. Period. Or temps spiral out of control. For any load greater than web browsing.

(Or am I the only guy running PrimeGrid on his Ryzen CPU?)
 
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Hans Gruber

Platinum Member
Dec 23, 2006
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I am not taking sides here. If you are running server grade software on home CPU's with a stock cooler. You are asking for trouble. If your memory is OC'd or not very stable all hell can break loose and you will get blue screens. Remember this. AMD said the 1600/2600/3600 has the cores that couldn't pass the test for the high level CPU certifications. They still work but you have to throw a lot of voltage at them. So for those who believe AMD developed some advanced algorithm to manage cooling on CPU's. I call bull shit on that one. If you think i am wrong, I give you Vega 64. They throw a bunch of voltage at that chip because some of the cores are broken but they still work with lots of voltage. Why do you think so many lower their voltage and get better performance. Because they didn't bin the chips, they simply said this was top of the line GPU and they throw a lot of voltage at it so the good and bad cores work. People wonder why the Vega 64 under volts so well.

My 3600 is running on a 240mm AIO. I said screw it and push 1.4v through it. Not one crash or blue screen after I dialed in the memory timings on the CJR Hynix sticks. I switched back from the E-die kit.

If people think 1.4v is a lot. Watch your Vcore in CPU-z stay well above 1.4v under heavy load. People would argue that is only for a short period of time. I would argue that a desktop PC is not a laptop. We don't have handicapped cores like in laptop or power saving features in desktops.

On a side note, a fairly young kid (early 20's) told me his vcore on his 7700K. 1.3v with a 212+. He was getting temps @ 1.3v 4.8ghz @ 100C on cores while gaming. Usually high 90's. I asked how long have you been running it like that. He said over a year. I said get a 240mm AIO because you already destroyed your CPU which had never blue screened on him all that time with a 1.3v on air. I should add that he listened to my advice and bought a Cooler Master 240mm AIO RGB. His max temp now on the hottest core is 79C on 1.275v.
 
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VirtualLarry

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How about posting a pic of your setup and where the case is located?

$20 says Larry has his PC in a air-restricted cubby again...
No, I took it out of the cubby, and even took the side panel off. Still, 95C+, crashed and black-screened, didn't even reboot, just froze.

AMD's "thermal throttling" is a joke.
 

VirtualLarry

No Lifer
Aug 25, 2001
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My 3600 is running on a 240mm AIO. I said screw it and push 1.4v through it.
AIO for AM4? Good plan! They should ship them that way.

On a side note, a fairly young kid (early 20's) told me his vcore on his 7700K. 1.3v with a 212+. He was getting temps @ 1.3v 4.8ghz @ 100C on cores while gaming. Usually high 90's. I asked how long have you been running it like that. He said over a year. I said get a 240mm AIO because you already destroyed your CPU which had never blue screened on him all that time with a 1.3v on air.
That's because, unlike AMD, Intel's thermal-throttling actually WORKS.

Edit: With Ryzen, get above 85C or thereabouts, you don't know if it's throttling, or if it's just going to blue-screen, black-screen, or freeze or reboot. It could do any of the above, once temps rise higher.

Edit: BTW, my main rig has a CM 240mm AIO. Running PrimeGrid on all 12 threads of my 3600, my max Package Temp under water is 89C. Not overclocked (on cores/voltage), but running FCLK 1800, DDR4-3600 (XMP).
 

Hans Gruber

Platinum Member
Dec 23, 2006
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No, I took it out of the cubby, and even took the side panel off. Still, 95C+, crashed and black-screened, didn't even reboot, just froze.

AMD's "thermal throttling" is a joke.
Larry, I listened to bad advice by Gamers Nexus to put AIO on front mounted on the bottom of the case. Somehow my AIO pump came loose. My temps were 95C + and my 3600 throttled down to 550mhz because of the heat. Remounted my AIO to top mounted, tubes do not stretch that way and my temps are back to mid 40's as I write this.

Check your mount to make certain it did not come loose.

I should note that Gamers Nexus said that you should have your pipes on the bottom of a front mounted AIO. I was transferring my computer from a P400 plastic window to a P400 tempered glass case. I figured it was BS and gave it a shot. No improvement and what was worse, most AIO do not have pipes long enough to have pipes on the bottom. I guess because I stretched it pretty far that it somehow came loose. Flip it back to pipes on top and running smooth again.


I liken this theory to water swirling backwards in a toilet in the southern hemisphere.
 
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StefanR5R

Elite Member
Dec 10, 2016
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Most AMD Ryzen processors have these two modes (and more):
  • AMD's defaults (as opposed to mainboard vendor's BIOS defaults):
    This one is to look good on paper, and to try a little bit of gaming and Geekbench runs on it.
  • ECO mode:
    This one is to use the CPU for actual computations.
 

TheGiant

Senior member
Jun 12, 2017
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Serious question. I've got a 65W-rated TDP Ryzen R5 1600, in a rig, on a 65W-rated AMD stock heatsink. It's blue-screening, crashing, and the CPU temps just keep going up and up.

I updated HWMonitor, and it's showing a "Package Power" for the entire chip, at 82W or so. No wonder it's constantly overheating and crashing. 82W TDP CPU > 65W TDP Heatsink.

The worst part is, this is AFTER limiting the number of PrimeGrid threads, down from 12 to 9. That's right, I'm not even running the CPU at a full thread load.

Edit: Yes, I know that the obvious answer, is to "get a better heatsink", and that the "stock heatsink" for the 1600 was the 95W TDP model. Which, at the time, was stated that AMD wanted to give users the ability to OC on the stock heatsink. Now I know that was a lie, it's because AMD CPUs (at least, the 1600), are NOT able to stay within their stated rated specs.
I am gonna repeat myself - TDP has zero value today
TDP as design was a number representing heat flow density- power/area considering heat spots as AVX units etc while doing the worst heat flow workload
today as an exact value without knowhow what it really represents has no value
the buying decision is the same- buy a new cooler or you are done
it was the same with my celeron 300A, the same with p4 2.4, the same with a64, the same with core 2 duo and the same with 3900X (the crap cooler)
 

rancherlee

Senior member
Jul 9, 2000
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What's it trying to clock to and how many volts is it pushing? I played around with the stock cooler on my 1600 (14nm Zen1) for awhile until my AM4 mounts showed up for my 140mm AIO. It ran ~3.2ghz @ 1.18v All core churning though hours of Prime and stayed in the low 80's with the fan screaming on the stock cooler, though with Arctic Silver instead of the factory pad.
 

maddogmcgee

Senior member
Apr 20, 2015
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Seems a pretty funny thing to get so angry about. Prime Grid seems pretty specialised and not an essential program for anyone. If it doesn't work for you, move on and use the computer for whatever stuff you actually do.
 

DrMrLordX

Lifer
Apr 27, 2000
21,620
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PrimeGrid

There's your problem. You're running an undersized HSF on the thing and trying to run PrimeGrid? Cmon, just undervolt it and set it to static clocks if you're going to do that. Disabling threads? Turn in your PC tuner card. Or try 1.2v and see what clocks you can sustain (I'm guessing 3.5-3.6 GHz in that workload).
 

amrnuke

Golden Member
Apr 24, 2019
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No, I took it out of the cubby, and even took the side panel off. Still, 95C+, crashed and black-screened, didn't even reboot, just froze.

AMD's "thermal throttling" is a joke.
Michelin make very good tires. Specifically, they make a great series of track day tires, the Pilot Sport series, rated for 186mph. They handle well, brake well, and are a spectacular track day tire.

You were looking for tires, and you knew Michelin made some that are great. So you bought a set of Michelins. A nice set of affordable Latitudes.

The problem is that you paid for the Latitude and you're expecting the Pilot Sport Cup 2. They're both Michelins, right? They should both be able to handle similar tasks thrown at them! Wrong. The Latitudes can't go as fast without risking failure, and to boot, they also don't handle as well in the corners. But they're quieter and better in the rain and far more practical for most people.

Your 1600 is a Michelin Latitude. It is far more practical for most people. Don't expect it to be a Pilot Sport Cup 2. If you want a track day CPU, buy a track day CPU.
 

alexruiz

Platinum Member
Sep 21, 2001
2,836
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Serious question. I've got a 65W-rated TDP Ryzen R5 1600, in a rig, on a 65W-rated AMD stock heatsink. It's blue-screening, crashing, and the CPU temps just keep going up and up.

I updated HWMonitor, and it's showing a "Package Power" for the entire chip, at 82W or so. No wonder it's constantly overheating and crashing. 82W TDP CPU > 65W TDP Heatsink.

The worst part is, this is AFTER limiting the number of PrimeGrid threads, down from 12 to 9. That's right, I'm not even running the CPU at a full thread load.

Edit: Yes, I know that the obvious answer, is to "get a better heatsink", and that the "stock heatsink" for the 1600 was the 95W TDP model. Which, at the time, was stated that AMD wanted to give users the ability to OC on the stock heatsink. Now I know that was a lie, it's because AMD CPUs (at least, the 1600), are NOT able to stay within their stated rated specs.

Something in your build is defective.
A Ryzen 5 1600 AE is perfectly cooled by the wraith stealth, even though it was bundled with a spire
A Ryzen 5 AF is bundled with the stealth, and runs cooler than the AE.
If your system is crashing is not the cooler, your build has a defective part.
 

StefanR5R

Elite Member
Dec 10, 2016
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I listened to bad advice by Gamers Nexus to put AIO [...]
I haven't watched the video. But from a look at the description below the video, he presumably discusses that the cooling loop must be mounted such that air pockets cannot build up where they could cause damage. *If* so, then this is sound advice in principle. Which coolers would be prone to air build-up in which orientation is obviously dependent on the particular cooler model.

--------

Seems a pretty funny thing to get so angry about. Prime Grid seems pretty specialised and not an essential program for anyone.
You're running an undersized HSF on the thing and trying to run PrimeGrid?
If you want a track day CPU, buy a track day CPU.
I disagree with these assessments.

PrimeGrid is a workload which any CPU at default settings, with a cooler which is sized and operated as specified by the CPU vendor (which includes parameters such intake air temperature) needs to run stable and return correct results. (I don't know whether or not @VirtualLarry's setup complies with AMD's specs.)

AMD specifies the Thermal Design Power with 65 W, but at the same time configures the Package Power Tracking target higher than the TDP. This is the central problem. *Why* is AMD doing that? They should not. It's idiocy. My guess is they do it because their competitor does it (and goes about it even worse than AMD). And then there are BIOS vendors who love to make it all even much worse with their own settings.

By the way, while the firmware of EPYCs have separate values for TDP and PPT too, AMD sets these to the same value by default (in the SKUs which I am aware of).
 

Hitman928

Diamond Member
Apr 15, 2012
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Can't you just turn off XFR/Precision boost and it will stick to TDP?

It also sounds like there might be something else going wrong with your system as the CPU should 100% be down clocking itself when reaching thermal thresholds to a stable frequency. Unless, as someone mentioned, something is wrong with your mount and the chip isn't really being cooled at all.
 
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MrTeal

Diamond Member
Dec 7, 2003
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Are you running with a restricted custom fan profile? Even pulling 88W, you shouldn't be getting up to thermal limits with a Wraith Spire if the fan is running full out unless there's an install issue or your ambient is crazy hot.
 

UsandThem

Elite Member
May 4, 2000
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AIO for AM4? Good plan! They should ship them that way.
Or buy an aftermarket cooler for any CPU, Intel or AMD, if you're going to use it the way you are using your PCs.

Running a heavy non-stop load (like PrimeGrid) and using a stock cooler is not what Intel or AMD has designed the stock coolers for. They are perfectly fine for how most people use their PCs for, and the "average joes" aren't pegging it at a constant100% doing things like mining for crypto or PrimeGrid. And for users who do that kind of thing, they buy an aftermarket cooler (AIO or air).
 

Markfw

Moderator Emeritus, Elite Member
May 16, 2002
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Or buy an aftermarket cooler for any CPU, Intel or AMD, if you're going to use it the way you are using your PCs.

Running a heavy non-stop load (like PrimeGrid) and using a stock cooler is not what Intel or AMD has designed the stock coolers for. They are perfectly fine for how most people use their PCs for, and the "average joes" aren't pegging it at a constant100% doing things like mining for crypto or PrimeGrid. And for users who do that kind of thing, they buy an aftermarket cooler (AIO or air).
Exactly. I may run 100% 24/7, but I have AIO's or top of the line air on all 18 systems, and none in enclosed spaces and all with the side cover odd, and only one GPU in each. You (@VirtualLarry )violate most every one of those rules from what I have read.
 
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Velgen

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Feb 14, 2013
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Larry, I listened to bad advice by Gamers Nexus to put AIO on front mounted on the bottom of the case. Somehow my AIO pump came loose. My temps were 95C + and my 3600 throttled down to 550mhz because of the heat. Remounted my AIO to top mounted, tubes do not stretch that way and my temps are back to mid 40's as I write this.

Check your mount to make certain it did not come loose.

I should note that Gamers Nexus said that you should have your pipes on the bottom of a front mounted AIO. I was transferring my computer from a P400 plastic window to a P400 tempered glass case. I figured it was BS and gave it a shot. No improvement and what was worse, most AIO do not have pipes long enough to have pipes on the bottom. I guess because I stretched it pretty far that it somehow came loose. Flip it back to pipes on top and running smooth again.


I liken this theory to water swirling backwards in a toilet in the southern hemisphere.

Think you may of missed the point of that video what it was talking about is that you should always mount the radiator such that the pump is at the bottom of the loop assuming your pump is in the block like it is in most AIOs. The reason is as another poster stated to avoid air bubbles getting in the pump causing issues. Believe the video recommends top mounting always if possible because that ensures that the pump will always be on the bottom (assuming the pump is in the block), but if your case does not support a radiator up top you can front mount just make sure the tubes for your block and radiator are positioned at the bottom. Whether you can do that with your case is a different matter.

As far Larry's issue my recommendation would be to get an aftermarket cooler simply because running a CPU at 100% doing any kind of long term workload on the stock cooler worries me. The stock coolers are generally just BARELY capable of handling 100% loads for their rated TDP they are generally not designed to be running at that for long periods of time. Case airflow as well as ambient air temperature could easily cause issues in that scenario. Haven't had any issues with my Ryzen CPUs blue screening/crashing due to thermal limits though and I generally have them running a bit hotter than most because I would prefer the lower noise from not running my fans quite as high. Also want to say mine thermal throttle themselves fine I think, but at the same time I don't believe I run any of mine in a situation that actually causes them to thermal throttle so may be wrong on that. Just want to say I saw throttling under a stress test before I adjusted my fan profile a bit, but I can't 100% remember.
 

VirtualLarry

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Aug 25, 2001
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Something in your build is defective.
A Ryzen 5 1600 AE is perfectly cooled by the wraith stealth, even though it was bundled with a spire
A Ryzen 5 AF is bundled with the stealth, and runs cooler than the AE.
If your system is crashing is not the cooler, your build has a defective part.


Have you run a Ryzen R5 1600 on wraith stealth? For more mundane, "normal" tasks, like web browsing, sure, it works fine.

But try running PrimeGrid, 12 threads of pure AVX2 torture for the CPU. :p The Package Power is over 80W, and termps on a 65W TDP heatsink, will just go up, and up, and up.