Question AMD Ryzen 3950X boost behavior

[Kocicak]

My 3950X I got today seems to have a weaker chiplet in it or I have no idea what is happening. First 8 cores routinelly boost over 45x, the second 8 never hit 44. Did I get a lemon (again)? I am attaching HWmonitor screenshot after few minutes of running light load.

BTW after a few minutes of running after I screenshotted it, 2 of the second 8 cores hit 4341, they are not all the same as you can see in the picture.

 

[amrnuke]

Actually I payed 950 USD incl. VAT for it and I DO WORRY ABOUT THE DETAILS. So far it seems it has one very quick chiplet with 2 cores hitting sometimes 4.7 GHz and the second one slow never reaching 4.4 GHz. I expected to get TWO very quick chiplets for that kind on money, not just one.

One more screenshot of the CPU doing almost nothing.

View attachment 13666

Perfect. So you worry about the details.

First, I recommend HWInfo or Ryzen Master over HWMonitor.

Second, I suggest you do a TON of reading on chip/chiplet design, AMD boost behavior, importance of cooling, and so on with reference to these chips rather than just looking at GHz and getting mad. What are you cooling it with? Did you get a water cooler like AMD recommended?

Third, I don't understand why you're upset. You have good base clocks (0.1GHz higher than advertised on all cores!), and you get 4.7 GHz boost as advertised. They DID NOT advertise 4.7 GHz all-core. If you expected that, it's your fault.

Fourth, you need to do more work to "prove" you have a bad chiplet before you toss in the towel. See @DrMrLordX post above.

As an aside, when I run CB20 my all-core speed on 3600 is <4GHz and yet my CB20 MT score is higher than a stock 8-core 1700X. GHz isn't everything.

 

[Kocicak]

I will test it again with the affinity settings.

I am using the AMD stock DISCO cooler, which keeps the CPU under 70°C in R20, I have no idea why they did not pack it in. I got stupid block of foam instead.
Cooling is not relevant for light load, because the CPU is cool anyway.

 

[UsandThem]

I am not "pissed off about AMD", I am just surprised that one half of the CPU runs much slower than the other half. In case this is typical for this product, I believe it is the best for everybody so that the producer himself informs consumers about this.

If could be actually a way to promote the product, if could easilly be that both of the chiplets are highly binned, one for speed and one for energy efficiency.

People here have told you over and over and over and over how the Ryzen 3000 series boosts. On top of that, have you actually taken 10 minutes to read a detailed review of CPUs like the 3900X and 3950X? I don't think you do, because you claim you bought the 3950 the day it launched, and then you immediately came here to create another garbage thread. Here is a detailed Anandtech article published on Nov 21: Best Core article

You ignore anyone who explains to you how they work in detail, and say things like you are "disappointed", "got a lemon", CPU was "defective", etc. I honestly don't think you are even being serious with the "woe is me" threads. I think we are being Rick rolled.

 

[amrnuke]

I will test it again with the affinity settings.

I am using the AMD stock DISCO cooler, which keeps the CPU under 70°C in R20, I have no idea why they did not pack it in. I got stupid block of foam instead.
Cooling is not relevant for light load, because the CPU is cool anyway.

At light load, there would be no reason for the chip to choose to put high frequency loads on a second chiplet. AMD bins their cores and chiplets and preferentially uses one over the other for lightly threaded work. Even in heavy work, such as CB20 single-thread, it alternates between my core 1 and core 2. Just because it doesn't use core 5 doesn't mean core 5 is a dud. In fact, it boosts just as high as the others. But AMD set preferred cores, that's just what happens.

You need to do some more exploration.

 

[uzzi38]

I will test it again with the affinity settings.

I am using the AMD stock DISCO cooler, which keeps the CPU under 70°C in R20, I have no idea why they did not pack it in. I got stupid block of foam instead.
Cooling is not relevant for light load, because the CPU is cool anyway.

Excuse me what the f-?

You do realise the 3950X doesn't come with a stock cooler, right? What's more, it doesn't come with a stock cooler and they also suggest to use the chip with a beefy AIO for a bloody reason.

You need something bigger not to keep the chip as a whole cool, but because of the heat density of the 3950X. The stock cooler is enough to cool the chip well, but to provide enough headroom for the algorithm to want to try boost higher? Nope. Not enough.

 

[Topweasel]

How could you be using the stock cooler if the 3950x doesn't come with one? Or I am wrong, this is the second person I have read suggesting there is a stock cooler.

What were the testing methods? Did you turn off assignments to the first CCD when checking activity on the second CCD? Was the CPU already well up to temp when you started using the second CCD? I could go on. Did you test it before the recent updates (those came out right). I admit I don't think I ever saw a core get 4.6 on my 3900x, but I know I saw a couple hit 4.5 max when I check RM's peaks after a few hours of usage.

The point is it can go on an on. The 4.7 isn't a sustained load. You seeing even two cores hit it at all is pretty damn impressive. You obviously do not like how AMD has designed their boost (modeled after theirs and Nividia's GPU boost behavior) to maximize performance early (go quicker early, finish quicker).

This discussion really needs to end on this. AMD doesn't make great overclockers. Why? Because they have developed a boost system that allows them to wring every last performance out of their Silicon. You want a CPU that has generic boosting settings and some head room for overclocks. Get a 9900K or 10980xe. If you want a core heavy weight mainstream CPU that even with its odd boost behavior either gives those chips a run for its money, or thrashes them. Then keep the 3950x.

If you want to talk more of the boost behavior. Read up on it first. And don't assume that because you don't understand it, it is either not working correctly, or you got a "dud". There is room to talk about it. Room even to criticize certain aspects of it. But coming in hot like that is starting to sound very trollish.

 

[Kocicak]

Ok, when I force one R15 thread on the second chiplet, the maximal frequency is 4391MHz (before that it was 4341).

1T R15 score on the first chiplet is 212 and on the second 203.

AMD Disco Cooler is sometimes called Wraith Prism and it does not come with 3950X. I bought it extra. 3950X comes with FOAM.

When running light load, CPU voltage reaches 1.50V

 

[uzzi38]

Ok, when I force one R15 thread on the second chiplet, the maximal frequency is 4391MHz (before that it was 4341).

1T R15 score on the first chiplet is 212 and on the second 203.

AMD Disco Cooler is sometimes called Wraith Prism and it does not come with 3950X. I bought it extra. 3950X comes with FOAM.

When running light load, CPU voltage reaches 1.50V

So when AMD choose to not box the CPU with the Prism, but on top of that also suggest using an AIO, why do you decide to avoid that and go with what would be the box cooler again?

 

[Thunder 57]

Ok, when I force one R15 thread on the second chiplet, the maximal frequency is 4391MHz (before that it was 4341).

1T R15 score on the first chiplet is 212 and on the second 203.

AMD Disco Cooler is sometimes called Wraith Prism and it does not come with 3950X. I bought it extra. 3950X comes with FOAM.

When running light load, CPU voltage reaches 1.50V

Higher frequencies (light load) require higher voltage. Doesn't come with a cooler? Sounds like a lot of Intel chips! Water cooling recommended? Screw that! Stop your bitching.

 

[kawi6rr]

Clearly this guy is getting a check from Intel can we just lock this thread already?

 

[Thunder 57]

Reviews came out about two weeks ago. You knew it would not come with a HSF. You knew they recommended liquid cooling. Stop crying about FOAM.

 

[Kocicak]

Water cooling for "normal operation" is not necessary, I said earlier, the cooler maintained below 70°C in R20 and I was getting results very similar to those in reviews.

Only if I wanted to squeeze every bit of performance out of this chip or overclock it, water cooling would be needed.

The CPU adjusts voltage and frequency according to the load, now it runs Prime95 at 0.919V and 3200 MHz, consuming 120W at temperature 68°C. The cooler is pretty silent too.

It just happily purrs under that air cooler and I have no reason to push it more.

 

[uzzi38]

Reviews came out about two weeks ago. You knew it would not come with a HSF. You knew they recommended liquid cooling. Stop crying about FOAM.

Erm, wrong person? I'm certainly not crying about a thing.

 

[Thunder 57]

Erm, wrong person? I'm certainly not crying about a thing.

Yup, sorry. I removed the quote.

 

[Thunder 57]

Water cooling for "normal operation" is not necessary, I said earlier, the cooler maintained below 70°C in R20 and I was getting results very similar to those in reviews.

Only if I wanted to squeeze every bit of performance out of this chip or overclock it, water cooling would be needed.

The CPU adjusts voltage and frequency according to the load, now it runs Prime95 at 0.919V and 3200 MHz, consuming 120W at temperature 68°C. The cooler is pretty silent too.

It just happily purrs under that air cooler and I have no reason to push it more.

Then be happy with what you've got. Enough already!

 

[UsandThem]

You do realise the 3950X doesn't come with a stock cooler, right? What's more, it doesn't come with a stock cooler and they also suggest to use the chip with a beefy AIO for a bloody reason.

AMD Disco Cooler is sometimes called Wraith Prism and it does not come with 3950X. I bought it extra. 3950X comes with FOAM.

So when AMD choose to not box the CPU with the Prism, but on top of that also suggest using an AIO, why do you decide to avoid that and go with what would be the box cooler again?

Someone got caught in the details.

You bought a Wraith Prism cooler separately? Yeah, I'm just not buying it.

From what I know, AMD doesn't sell that cooler in the retail channel. Sure you can buy it used from people not using the stock cooler, although at the price 3rd party sellers charge for it, you can get a much better cooler.

"Never gonna give, never gonna give"...........

 

[Kocicak]

Enough already!

Pardon? You do not say this in real life to grown people, do you?

If you do not like what I write, please do not visit this thread again.

Thank you.

 

[Kocicak]

You bought a Wraith Prism cooler separately? Yeah, I'm just not buying it.

From what I know, AMD doesn't sell that cooler in the retail channel. Sure you can buy it used from people not using the stock cooler, although at the price 3rd party sellers charge for it, you can get a much better cooler.

Yes, AMD sold this cooler separatelly, but I got it from somebody not using it for 3800X for 13 USD. Retail was around 40 USD incl VAT.

 

[Thunder 57]

Pardon? Do do not say this in real life to grown people, do you?

If you do not like what I write, please do not visit this thread again.

Thank you.

I don't like what you write because you are full of crap! I'll never say you should be silenced, as I want to hear different points of view. All you have done is to prove that either you hate AMD, hate capitalism, love Intel, or are just someone who can't be happy with anything.

 

[Thunder 57]

Pardon? You do not say this in real life to grown people, do you?

If you do not like what I write, please do not visit this thread again.

Thank you.

Why do you keep buying AMD CPU's if you are constantly disappointed with them?

 

[Kocicak]

I bought the best CPU available for very high (at least for me) price, and I am not allowed to ask, why half of it runs notably slower than the other half? Really? Are you guys really serious???

Some of you guys behave irrationally and some of you are even so rude, that you are probably breaking the rules of this forum.

I don't like what you write because you are full of crap!

Is english you native language? Because this is really unacceptable.

 

[UsandThem]

I bought the best CPU available for very high (at least for me) price, and I am not allowed to ask, why half of it runs notably slower than the other half? Really? Are you guys really serious???

You are allowed to post your thoughts, and we are afforded the same right.

You posted this exact same thing about the 3900X, and you saw what happened in that thread. Yet you decided to post the same thing about the 3950X and expected a different outcome?

You're the one who has called both CPUs "duds" (and even returned your 3900X), yet you don't seem to know how Ryzen2 CPUs work. The CPU sub-forum has some people who are really into CPU architecture and technical discussion, so when you make bold claims like you have many times, you're not going to have a good day.

 

[Markfw]

I bought the best CPU available for very high (at least for me) price, and I am not allowed to ask, why half of it runs notably slower than the other half? Really? Are you guys really serious???

Some of you guys behave irrationally and some of you are even so rude, that you are probably breaking the rules of this forum.


Is english you native language? Because this is really unacceptable.

The CPU is running the way it was designed. Not the way YOU think it should work.
Everybody here is sick of your garbage posts. Some are less politically correct how they say it.

 

[Kocicak]

3900X was not hitting the advertised boost frequency at all. HALF of this 3950X works as advertised and as I expected, the other half surprised me. 300 MHz is quite a notable difference.

 

[Thunder 57]

3900X was not hitting the advertised boost frequency at all. HALF of this 3950X works as advertised and as I expected, the other half surprised me.

You don't know what you're talking about. Buy Intel!!!