Review AMD Ryzen 9 3950X Review: 16 Cores Muscles Into the Mainstream

joeblowsmynose

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in the compression section ...

" ... 2900WX ..." should be 2990WX

Also, does power consumption not equate to cooling requirements? Why do we seem to have the 3950x drawing vastly less power than a 9900k @5.0ghz, (by about 50%) and about roughly the same as the 3900x, but the sentiment seems to be that this chip is very hard to cool, but that sentiment isn't raised with the other chips? Why this disparity?

With the 9900k @5.0 drawing 50% more power, is it 50% more difficult to keep cool at that OC or is there some magic happening here that just causes the 3950x to output more heat, despite the power consumption? (I don't have a 9900k so I have no personal experience with its cooling requirements)

And thank you for using a cooler people would actually buy for the testing purposes (outside the manual OC results). I think this is important. The more exotic cooling results are nice to see, but only as a supplement to real-world expectations, IMHO.
 
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joeblowsmynose

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From the value perspective, it seems like the 3900x is super compelling. Thoughts?

That's the one I will be getting - best bang for buck for what I need my CPU to do. I'll be waiting a little bit longer though to ensure the supply issue is 100% gone. The reason for this is that I think the 3900x became mired in the "boost clock" issue much more so than the other chips was that they may have slightly lowered their binning specs with the 3900x to be able to produce more useable chips against the very high demand for them.

I have no evidence other than the boost clock issues with the 3900x, but I just want to be sure I'm getting the silicon exactly as it was initially intended. I could be wrong, but its just a precaution I am taking. Besides, we might see some deals popping up on them soon as well.
 
in the compression section ...

" ... 2900WX ..." should be 2990WX

Also, does power consumption not equate to cooling requirements? Why do we seem to have the 3950x drawing vastly less power than a 9900k @5.0ghz, (by about 50%) and about roughly the same as the 3900x, but the sentiment seems to be that this chip is very hard to cool, but that sentiment isn't raised with the other chips? Why this disparity?

With the 9900k @5.0 drawing 50% more power, is it 50% more difficult to keep cool at that OC or is there some magic happening here that just causes the 3950x to output more heat, despite the power consumption? (I don't have a 9900k so I have no personal experience with its cooling requirements)

And thank you for using a cooler people would actually buy for the testing purposes (outside the manual OC results). I think this is important. The more exotic cooling results are nice to see, but only as a supplement to real-world expectations, IMHO.

Cooling a CPU is not always related to power use.

And they have been using the H115i for most tests, only using the more exotic setups for high end overclocking.
 
"Limited overclocking headroom"
Okay, should this REALLY be a con for this cpu considering its use case(affordable professional level cpu, sans the extra pcie lanes)?

Considering it is an enthusiast CPU, yes. Overclocking is a core of the enthusiast platform. Hell it used to be one of AMDs biggest points was that all their CPUs could overclock on all boards. But with Ryzen its been limited due to the CPUs being clocked to the upper limit.
 

joeblowsmynose

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Cooling a CPU is not always related to power use.
How and why? (detailed explanation or links to references will do - I am most interested in the deltas, but any explanations would also be nice)

And they have been using the H115i for most tests, only using the more exotic setups for high end overclocking.
Temp graphs would be useful then -- assuming they used the same cooler for all the test - which I think they should try to do just so we can see. I have a feeling the 9980XE OC numbers weren't using that cooler though ... I like to know where the comparitive limits are - I find that useful info.
 

joeblowsmynose

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"Limited overclocking headroom"
Okay, should this REALLY be a con for this cpu considering its use case(affordable professional level cpu, sans the extra pcie lanes)?

I think its valid ... but that con should also apply to the 9900KS as well. It seems while Tom's was able to hit 5.2 with 720mm of rad custom loop setup, is a bit of an outlier exception - everyone else seemed to get a max of 5.1 at best (stable). BitWit (youtube tech guy) actually found his 9900k was better binned than his 9900ks.
 
That's the one I will be getting - best bang for buck for what I need my CPU to do. I'll be waiting a little bit longer though to ensure the supply issue is 100% gone. The reason for this is that I think the 3900x became mired in the "boost clock" issue much more so than the other chips was that they may have slightly lowered their binning specs with the 3900x to be able to produce more useable chips against the very high demand for them.

I have no evidence other than the boost clock issues with the 3900x, but I just want to be sure I'm getting the silicon exactly as it was initially intended. I could be wrong, but its just a precaution I am taking. Besides, we might see some deals popping up on them soon as well.

That is not the case at all, they definitely did not sacrifice quality of a 500$ chip to please people, that would've been counter-intuitive and AMD is not dumb enough to make that sacrifice. I got mine in Sep, after the first batch sold out so it was in the second batch. And I am able to get 4.2GHz at 1.25V stable. No sacrifices should have been made to increase production speed. Poeple pay good money for their devices, and AMD is already facing the FX lawsuit, they don't need a bigger one on their hand.

Though I do understand your cautious thinking.
 
in the compression section ...

" ... 2900WX ..." should be 2990WX

Also, does power consumption not equate to cooling requirements? Why do we seem to have the 3950x drawing vastly less power than a 9900k @5.0ghz, (by about 50%) and about roughly the same as the 3900x, but the sentiment seems to be that this chip is very hard to cool, but that sentiment isn't raised with the other chips? Why this disparity?

With the 9900k @5.0 drawing 50% more power, is it 50% more difficult to keep cool at that OC or is there some magic happening here that just causes the 3950x to output more heat, despite the power consumption? (I don't have a 9900k so I have no personal experience with its cooling requirements)

And thank you for using a cooler people would actually buy for the testing purposes (outside the manual OC results). I think this is important. The more exotic cooling results are nice to see, but only as a supplement to real-world expectations, IMHO.

Linus tech tips got the same power conclusions; 3950x being a little better than the 3900x, but he got results of cooler temps compared to the 3900x. An avg of 71c on full stress with stock settings. I think they used the wraith cooler that comes with the 3900x because I'm using it for now and my 3900x gets the same temps he showed in their video.
 
How and why? (detailed explanation or links to references will do - I am most interested in the deltas, but any explanations would also be nice)


Temp graphs would be useful then -- assuming they used the same cooler for all the test - which I think they should try to do just so we can see. I have a feeling the 9980XE OC numbers weren't using that cooler though ... I like to know where the comparitive limits are - I find that useful info.


https://www.tomshardware.com/reviews/intel-core-i9-9980xe-cpu,5902-2.html

You can easily look it up. They used a H115i for the 9980XE, the 9900K and the 9900KS stock (not the 9900KS OC though).

As for the former, there is a lot of different factors. The process tech is one, the uArch design, the die size, the heatspreader design, the TIM etc. For example Intels 9th gen has a TJunction max of 100c. Per AMD the 3900X maxes out at 95c yet their FX series topped out at 65c yet the FX 8150 used way more power than the 3950X does.

How big is the die in order to dissipate the heat? The hotter a CPU gets the less clocking head room there is for boost clocks. AMD is recommending a beefy water cooling system in order for the chip to meet thermal requirements to hit boost speeds. You can probably use an air cooler but it might not be able to move the heat fast enough to keep it within thermal requirements.

I honestly think the process tech AMD uses holds some parts back since it was not designed just for high powered x86 CPUs. If they had their own design it may be different.
 

joeblowsmynose

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https://www.tomshardware.com/reviews/intel-core-i9-9980xe-cpu,5902-2.html

You can easily look it up. They used a H115i for the 9980XE, the 9900K and the 9900KS stock (not the 9900KS OC though).
Yeah I complained about the cooling setup for the KS review - not that they shouldn't have, but it should have only been a supplement to figures with a cooler most people would buy.

I mean they should include those in reviews as comparisons to others within the reviews - that would be useful.

As for the former, there is a lot of different factors. The process tech is one, the uArch design, the die size, the heatspreader design, the TIM etc. For example Intels 9th gen has a TJunction max of 100c. Per AMD the 3900X maxes out at 95c yet their FX series topped out at 65c yet the FX 8150 used way more power than the 3950X does.

How big is the die in order to dissipate the heat? The hotter a CPU gets the less clocking head room there is for boost clocks. AMD is recommending a beefy water cooling system in order for the chip to meet thermal requirements to hit boost speeds. You can probably use an air cooler but it might not be able to move the heat fast enough to keep it within thermal requirements.

I honestly think the process tech AMD uses holds some parts back since it was not designed just for high powered x86 CPUs. If they had their own design it may be different.

None of that would explain 3950x being hotter than say a 3900x though at the same wattage ... perhaps the implication wasn't meant to imply that the 3950x was any hotter than 3900x, but the "must have" water cooling, statement doesn't seem to apply to the 3900x - in fact it ships with a stock air cooler that suffices. That air cooler actually does suffice on the 3950x as another reviewer has attested to.

So there's still a sensed disparity that seems to have been a factor of the way things were written in the article.
 

joeblowsmynose

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That is not the case at all, they definitely did not sacrifice quality of a 500$ chip to please people, that would've been counter-intuitive and AMD is not dumb enough to make that sacrifice. I got mine in Sep, after the first batch sold out so it was in the second batch. And I am able to get 4.2GHz at 1.25V stable. No sacrifices should have been made to increase production speed. Poeple pay good money for their devices, and AMD is already facing the FX lawsuit, they don't need a bigger one on their hand.

Though I do understand your cautious thinking.

If they have a large number of chips, an excess perhaps, or being way ahead of the curve in terms of supply/demand, then you'll naturally get more high quality silicon that perhaps exceeds specs in the chips.

They don't bin to exactly an extremely specific number - they work in ranges of appropriateness for the chip to reach something specific as a minimum.

If you have a constrained supply, you are probably dragging as close to that bare minimum as possible to maximize production. If you don't have a constrained supply, you have more chiplets that will exceed the minimum spec by a larger margin.

We can already see that there is a little bit of variance between processors of the same sku in terms of boosting and max clocks. Those chips are bouncing off that minimum spec lower than others.

So I think my thoughts on this are sound. I wasn't trying to say that AMD would sell out of spec or defective chips just make the sale. I certainly wasn't implying that.
 
Yeah I complained about the cooling setup for the KS review - not that they shouldn't have, but it should have only been a supplement to figures with a cooler most people would buy.

I mean they should include those in reviews as comparisons to others within the reviews - that would be useful.



None of that would explain 3950x being hotter than say a 3900x though at the same wattage ... perhaps the implication wasn't meant to imply that the 3950x was any hotter than 3900x, but the "must have" water cooling, statement doesn't seem to apply to the 3900x - in fact it ships with a stock air cooler that suffices. That air cooler actually does suffice on the 3950x as another reviewer has attested to.

So there's still a sensed disparity that seems to have been a factor of the way things were written in the article.

They were going based on AMDs recommendation. Thats all they can do. Sure they can test it but if AMD is recommending better cooling there is a good reason for it.
 

joeblowsmynose

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They were going based on AMDs recommendation. Thats all they can do. Sure they can test it but if AMD is recommending better cooling there is a good reason for it.

"The 3950X comes with an AMD-defined 105W TDP just like the 3900X, but the four extra active cores require a more robust cooling solution. "

It looks like an extra 50mhz, maybe 100 with extremely good silicon in single core boost might be the reason (since Ryzen tends to boost variable based on cooling a little), not sure that's enough ... again, a high end noctua or even the 3900x stock cooler is adequate at stock.
 
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"The 3950X comes with an AMD-defined 105W TDP just like the 3900X, but the four extra active cores require a more robust cooling solution. "

It looks like an extra 50mhz, maybe 100 with extremely good silicon in single core boost might be the reason (since Ryzen tends to boost variable based on cooling a little), not sure that's enough ... again, a high end noctua or even the 3900x stock cooler is adequate at stocks.

You forget it has 4 additional cores which mean additional links to the I/O chips as well compared to the 3900X. That adds up and uses more power, one review I read showed the 3950X OCed to 4.3GHz was hitting 363W, just shy of the 9980XE, in power draw under load.

https://hothardware.com/reviews/amd-ryzen-9-3950x-zen-2-review?page=6

And again AMD is recommending liquid cooling:

https://www.amd.com/en/products/cpu/amd-ryzen-9-3950x

Thermal Solution (PIB)

Cooler Not Included, Liquid Cooling Recommended
 
You forget it has 4 additional cores which mean additional links to the I/O chips as well compared to the 3900X. That adds up and uses more power, one review I read showed the 3950X OCed to 4.3GHz was hitting 363W, just shy of the 9980XE, in power draw under load.

https://hothardware.com/reviews/amd-ryzen-9-3950x-zen-2-review?page=6

And again AMD is recommending liquid cooling:

https://www.amd.com/en/products/cpu/amd-ryzen-9-3950x

These three videos seem to suggest that the 3950x is not significantly harder to cool or uses significantly more power than the processors like the 3900x or 9900k at stock settings (Unless it is overclocked, which is really a moot point for Ryzen as you have pointed out yourself. It doesn't even gain much performance when manually tuned to the max).

View: https://www.youtube.com/watch?v=M3sNUFjV7p4

View: https://www.youtube.com/watch?v=stM2CPF9YAY&t=521s

View: https://www.youtube.com/watch?v=wmqT2-2seT0&t=1160s
 
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Thank you @TCA_ChinChin, I was literally typing the following the reply when you posted your message!

I'm with @joeblowsmynose: I don't believe the claim that the 3950X requires a more robust cooling solution is supported by the data. Toms, Gamers Nexus and Hardware Unboxed all found the 3950X matching or even coming in under the 3900X for sustained power draw. Sure, cooling requirements don't correlate perfectly to power draw, but surely no one is arguing that a 3950X pulling 145W somehow requires more cooling than a 3900X pulling the same power?

In fact, I don't want to sound fan-boyish here, but isn't it pretty remarkable that AMD have managed to get 33% more cores running without measurably increasing the power draw... all with only a slight drop to the base clock? Any increase in core count on the same process node without having to resort to ramping power or gutting clock speeds is laudable progress in my book. Correct me if I'm wrong, but the 3900X was never presented as a power hog, in fact, from my memory it was generally deemed an efficient processor for its target market. AMD hit the same power draw with 4 extra cores... almost exclusively (as far as I can tell) from better binning. The 3950X is straight up a more efficient and superior product.

OC it, and of course, all efficiency goes out the window. On top of that, performance gains through OCing are minimal at best. I agree that those who value the experience of overclocking and tweaking won't be particularly excited by the 3950X... fair criticism. But criticising power draw, efficiency and cooling requirements??? That seems like a criticism we were all expecting to be able to level, but where the 3950X has actually and quite impressively surpassed expectations and should have, IMHO, been praised for... not criticised.