Discussion Ryzen 9000X3D series review thread

[Indus]

I have a 9800X3D and I noticed in OCCT in the normal CPU and the Linepack 2021 stability tests that my CPU will stay at slightly over 4.7GHz then after 30 seconds or so drop a little below its 4.7GHz base frequency as it gets closer to its 95C Tjmax temperature and it gets closer to 4.6GHz than 4.7GHz about a minute of staying at the 95C Tjmax in these two tests. The Linepack 2019 stability test, my 9800X3D stays between 5 to 5.2 GHz even at the 95C Tjmax temperature and the same with Cinebench R20. I use a Noctura U12A CPU cooler to cool my 9800X3D. Should my CPU guarantee it's 4.7GHz base frequency, no matter what, since it's advertised with a 4.7GHz base frequency? I thought base clocks were guaranteed minimum clocks by the manufacturer of the CPU no matter what. During gaming, it is usually running at 5.2-5.25GHz.

This is not an AMD thing.. I have a few Intel CPU's and they all drop down to below base frequency when idling. My 12600k idles at 400mhz when I'm not using it that much..

Check CPUID. The bus speed never drops but the multiplier should drop depending on idle or use or gaming states.




You should be thankful it drops below the advertised speed because it saves you energy and electricity costs.. as people actually have run it at full speed all the time by changing it in bios settings and it then becomes an major drain on electricity.

Mostly a CPU will look at states of use and priority:
1. Is it being used? No - It'll idle.
2. Yes? If being used, how high can it go without overheating?
3. If it gets too hot, it'll throttle back.

 

[igor_kavinski]

Back in the time CPUs did not have a turbo boost feature and only a base clock, would they throttle below their advertised frequency if they started to overheat or reach a specific temperature or would they just continue to stay at their advertised frequency and eventually shutdown the system or kill the CPU due to overheating or would they throttle as well?

A CPU will maintain its base clock as long as your cooling solution is able to dissipate the heat properly. If not, it will throttle to keep the CPU from overheating and causing heat related damage. Regarding 7800X3D, it is prevented from going above 89C. If you want a fair comparison, reduce the 9800X3D's max temp to 89C from its default 95C.

By the way, official pages for both CPUs mention liquid cooler for optimal performance.

 

[Dave3000]

A CPU will maintain its base clock as long as your cooling solution is able to dissipate the heat properly. If not, it will throttle to keep the CPU from overheating and causing heat related damage. Regarding 7800X3D, it is prevented from going above 89C. If you want a fair comparison, reduce the 9800X3D's max temp to 89C from its default 95C.

I just set the Tjmax to 89C in the BIOS and the CPU frequency start at just over 4.7GHz and slowly dropped to just under 4.6GHz after 4 1/2 minutes in the normal CPU test in OCCT.

 

[igor_kavinski]

I just set the Tjmax to 89C in the BIOS and the CPU frequency start at just over 4.7GHz and slowly dropped to just under 4.6GHz after 4 1/2 minutes in the normal CPU test in OCCT.

There is the slight possibility that you got a bad sample but we really need someone else to test this with their 9800X3D.

 

[Dave3000]

Also I tested my 7800X3D and on the same test in OCCT it reached 77C and was between between upper 4.2GHz to lower 4.3GHz, which is still above its base clock. Why didn't my 7800X3D go faster if it there is PPT and Tjmax headroom to do so as it was well under the 89C Tjmax for the 7800X3D the whole time I tested it? My 9800X3d was most of the time around 138W in this test and my 7800X3D was most of the time around 74W in this test. Shouldn't my 7800X3D go as fast as it can in this test until it reached 89C Tjmax and is still within the default PPT range?

Do you have a 7800X3D? Another thing weird I noticed is that in OCCT latency/bandwidth benchmark, my 7800X3D shows much slower L3 cache bandwidth than my 9800X3D. My 7800X3D gets around 154MB/s read and 75MB/s write for L3 cache and my 9800X3D gets around 541MB/s read and 298MB/s write for L3 cache in this benchmark. In AIDA64, my 7800X3D is a little slower than my 9800X3D in the L3 cache benchmark, so I wonder if something is wrong with my 7800X3D that would cause the much lower L3 cache performance in OCCT than my 9800X3D. Maybe I also have a bad sample of my 7800X3D? Anyone else here with a 7800X3D have this weird issue in the L3 cache test in the latency/bandwidth benchmark in OCCT or should it be close to what the 9800X3D gets for L3 cache performance just like in AIDA64?

 

[igor_kavinski]

Why didn't my 7800X3D go faster if it had plently of TDP and Tjmax headroom to do so as it was well under the 89C Tjmax for the 7800X3D the whole time I tested it? My 9800X3d was most of the time around 138W in this test and my 7800X3D was most of the time around 74W in this test. Shouldn't my 7800X3D go as fast as it can in this test until it reached 89C Tjmax and is still within the default TDP range?

It is limited by the V-cache lying on top of the CCD. If it goes any faster, the cache will crash and burn.

9800X3D has the V-cache at the bottom of the CCD.

Do you have a 7800X3D? Another thing weird I noticed is that in OCCT latency/bandwidth benchmark, my 7800X3D shows much slower L3 cache bandwidth than my 9800X3D. My 7800X3D gets around 157MB/s read and 74MB/s write for L3 cache and my 9800X3D gets around 480MB/s read and 340MB/s write for L3 cache in this benchmark. In AIDA64, my 7800X3D is a little slower than my 9800X3D in the L3 cache benchmark, so I wonder if something is wrong with my 7800X3D that would cause the much lower L3 cache performance in OCCT than my 9800X3D. Maybe I also have a bad sample of my 7800X3D?

9950X3D. I can't test it right now (not hooked up) and hooking it up is a bit of an effort since it's normal configuration is backside ports towards the floor which makes plugging stuff in it challenging. Had to do it that way coz it's a small mATX case and I wanted the 240mm AIO to be on top.

7800X3D is 2nd generation V-cache. That's the best AMD could do at the time. I wouldn't care that much about the lower L3 performance. It's hard to be performant for that cache when it's literally being cooked by the CCD underneath it.

 

[Dave3000]

It is limited by the V-cache lying on top of the CCD. If it goes any faster, the cache will crash and burn.

9800X3D has the V-cache at the bottom of the CCD.


9950X3D. I can't test it right now (not hooked up) and hooking it up is a bit of an effort since it's normal configuration is backside ports towards the floor which makes plugging stuff in it challenging. Had to do it that way coz it's a small mATX case and I wanted the 240mm AIO to be on top.

7800X3D is 2nd generation V-cache. That's the best AMD could do at the time. I wouldn't care that much about the lower L3 performance. It's hard to be performant for that cache when it's literally being cooked by the CCD underneath it.

My concern is not with Ryzen 9000X3D series in this benchmark for L3 cache performance, so don't bother doing that.

 

[StefanR5R]

Why didn't my 7800X3D go faster if it there is PPT and Tjmax headroom

Besides limits to power and temperature, there are also limits to Voltages and currents.
AFAIU, the new X3D stacking of the 9000X3D series does not only improve thermal conduction from cores to cooler, but also allows for higher core Voltages compared to 5000X3D/7000X3D.

 

[Dave3000]

It is limited by the V-cache lying on top of the CCD. If it goes any faster, the cache will crash and burn.

9800X3D has the V-cache at the bottom of the CCD.


9950X3D. I can't test it right now (not hooked up) and hooking it up is a bit of an effort since it's normal configuration is backside ports towards the floor which makes plugging stuff in it challenging. Had to do it that way coz it's a small mATX case and I wanted the 240mm AIO to be on top.

7800X3D is 2nd generation V-cache. That's the best AMD could do at the time. I wouldn't care that much about the lower L3 performance. It's hard to be performant for that cache when it's literally being cooked by the CCD underneath it.

I also just tried OCCT 12.1.1.1 and 13.0 and each one shows way different results in the L3 cache benchmark.

It is limited by the V-cache lying on top of the CCD. If it goes any faster, the cache will crash and burn.

9800X3D has the V-cache at the bottom of the CCD.


9950X3D. I can't test it right now (not hooked up) and hooking it up is a bit of an effort since it's normal configuration is backside ports towards the floor which makes plugging stuff in it challenging. Had to do it that way coz it's a small mATX case and I wanted the 240mm AIO to be on top.

7800X3D is 2nd generation V-cache. That's the best AMD could do at the time. I wouldn't care that much about the lower L3 performance. It's hard to be performant for that cache when it's literally being cooked by the CCD underneath it.

Are you saying that the V-Cache is throttling the CPU because the V-Cache has a thermal throttle point for the CPU and it will throttle the CPU once the V-Cache reaches a specific temperature weather the CPU has plenty of thermal headroom and still well below its TDP limit on the Ryzen 7000X3D series? Is this like when low quality VRMs without heatsinks on a low-end motherboard can't handle higher frequencies at full loads on higher end CPUs and ends up thermal throttling for the VRMs too cool off even if the CPU has adequate cooling and well below its Tjmax?

 

[igor_kavinski]

Are you saying that the V-Cache is throttling the CPU because the V-Cache has a thermal throttle point for the CPU and it will throttle the CPU once the V-Cache reaches a specific temperature weather the CPU has plenty of thermal headroom and still well below its TDP limit on the Ryzen 7000X3D series?

AMD Ryzen 7 9800X3D Review - The Best Gaming Processor

The Ryzen 7 9800X3D establishes AMD as the leader in gaming performance. This Zen 5-based X3D chip is not only fast, it also comes with full support for overclocking. Besides gaming, application performance is considerably improved over the 7800X3D, but that comes at a price.

www.techpowerup.com

Clearly shows in the Blender workload that the 7800X3D has a lower temperature threshold. In gaming or lightly threaded workloads, the 9800X3D is faster in frequency and more efficient by virtue of better IPC so it doesn't need to burn more watts to get better performance than the 7800X3D.

 

[Dave3000]

It is limited by the V-cache lying on top of the CCD. If it goes any faster, the cache will crash and burn.

9800X3D has the V-cache at the bottom of the CCD.


9950X3D. I can't test it right now (not hooked up) and hooking it up is a bit of an effort since it's normal configuration is backside ports towards the floor which makes plugging stuff in it challenging. Had to do it that way coz it's a small mATX case and I wanted the 240mm AIO to be on top.

7800X3D is 2nd generation V-cache. That's the best AMD could do at the time. I wouldn't care that much about the lower L3 performance. It's hard to be performant for that cache when it's literally being cooked by the CCD underneath it.

The L3 cache on my 7800X3D only hits 43C during OCCT CPU stress test. Is 43C for L3 cache in the range of slowing down the core frequency of the CPU? I checked L3 cache temperature with OCCT's monitoring feature. Is that L3 cache temperature that OCCT is showing just for the normal part of L3 cache (32MB) and not temperature of the extended L3 cache (V-cache)? Was the V-cache itself most likely running much hotter than that on my 7800X3D?

Another thing is that my 9800X3D starts to slow down a little at around 91C and the closer it gets to its 95C Tjmax it slows down little by little. Shouldn't a Ryzen CPU only start to slow down once it hits its stock Tjmax, in this case shouldn't my 9800X3D keep running at 5200-5250 MHz during Linepack (2019) in OCCT until Tctl hits 95C and not drop at all below 4700MHz during the normal OCCT CPU stability test until Tctl hits 95C. My 9800X3D ends up dropping to around 5050-5080 MHz in Linepack (2019) in OCCT at around the 4-minute mark. What I'm saying is that I notice my 9800X3D starts to drop speed little by little at around 91C and not the stock target 95C and I'm not sure if that's normal for this CPU provided that it's staying within the default power limits.

 

[igor_kavinski]

Was the V-cache itself most likely running much hotter than that on my 7800X3D?

SRAM is supposed to function up to 85C. I don't know what the max operating temp is for V-cache. Could be a lot lower to prevent errors and/or to reduce sudden slowdown since once heavy error correction comes into play, the latency figures for the SRAM will start going up.

What I'm saying is that I notice my 9800X3D starts to drop speed little by little at around 91C and not the stock target 95C and I'm not sure if that's normal for this CPU provided that it's staying within the default power limits.

I think the reason you are seeing weird behavior is because you are using a stress test (LINPACK) which is supposed to heat up the CPU very much. AMD's figures are more likely stated for "normal use". Try using a real workload (even Cinebench) or my own Rudi_Float_Bench in my sig and report back on any difference in observed behavior of frequency/temps.

 

[Dave3000]

I tried Cinebench 23 and same behavior with CPU going below 5.2GHz all-core once hitting the low 90's and around 5.03 to 5.08GHz all-core at 95C at 50% into the run. My score in Cinebench 23 is around 22800-23000 after several random multiple runs. My case I'm using for my 9800X3D system is a Define 7 Compact with 2 140mm front intake fans and 1 120mm rear exhaust fan. My secondary PC is using the Meshify C and my primary PC is using the Define 7 Compact which I swapped out the stock fans with 2 Arctic 140mm intake and 1 Arctic 120mm exhaust. However, same behavior with CPU starting to throttle slowly once hitting 91C instead of running at full boost frequency until the 95C Tjmax. I think my 9800X3D ran a liitle cooler, as in boosted a little higher at the same temperature, in my Meshify C than my Define 7 Compact even with the same fans and fan configuration installed as scores in Cinebench 11, 20, and 23 are slightly better when using my Meshify C case. Still my main concern with why my 9800X3D starts to gradually throttle it's all-core frequency during CPU stress testing at 91C instead of staying at top boost frequency until its 95C Tjmax.

 

[Thunder 57]

I tried Cinebench 23 and same behavior with CPU going below 5.2GHz all-core once hitting the low 90's and around 5.03 to 5.08GHz all-core at 95C at 50% into the run. My score in Cinebench 23 is around 22800-23000 after several random multiple runs. My case I'm using for my 9800X3D system is a Define 7 Compact with 2 140mm front intake fans and 1 120mm rear exhaust fan. My secondary PC is using the Meshify C and my primary PC is using the Define 7 Compact which I swapped out the stock fans with 2 Arctic 140mm intake and 1 Arctic 120mm exhaust. However, same behavior with CPU starting to throttle slowly once hitting 91C instead of running at full boost frequency until the 95C Tjmax. I think my 9800X3D ran a liitle cooler, as in boosted a little higher at the same temperature, in my Meshify C than my Define 7 Compact even with the same fans and fan configuration installed as scores in Cinebench 11, 20, and 23 are slightly better when using my Meshify C case. Still my main concern with why my 9800X3D starts to gradually throttle it's all-core frequency during CPU stress testing at 91C instead of staying at top boost frequency until its 95C Tjmax.

Sounds normal to me. Unless you are trying to use it to boil water. Are you really concerned it starts to throttle 4 degrees before max? I mean doesn't have to start throttling a bit before 95 because otherwise it will be too late and go over it? Call me old school but 95C is too high. I set my max temp to 85.

 

[igor_kavinski]

Not to mention it's a bit unrealistic since you are not going to have the CPU running full tilt all the time. Also, as I've said before, AMD recommends a liquid cooler. The Liquid Freezer Pro is frequently on sale so get that if you are bothered by the throttling. I personally don't think there is anything wrong with your particular CPU sample. It's just doing whatever it needs to, to protect itself.

 

[StefanR5R]

Are you really concerned it starts to throttle 4 degrees before max? I mean doesn't have to start throttling a bit before 95 because otherwise it will be too late and go over it?

Fast temperature fluctuations (i.e. spikes which monitoring software doesn't show), or/and reaching other levels in the V/f/T control space might play into it too.

 

[Dave3000]

I tried Cinebench 23 and same behavior with CPU going below 5.2GHz all-core once hitting the low 90's and around 5.03 to 5.08GHz all-core at 95C at 50% into the run. My score in Cinebench 23 is around 22800-23000 after several random multiple runs. My case I'm using for my 9800X3D system is a Define 7 Compact with 2 140mm front intake fans and 1 120mm rear exhaust fan. My secondary PC is using the Meshify C and my primary PC is using the Define 7 Compact which I swapped out the stock fans with 2 Arctic 140mm intake and 1 Arctic 120mm exhaust. However, same behavior with CPU starting to throttle slowly once hitting 91C instead of running at full boost frequency until the 95C Tjmax. I think my 9800X3D ran a liitle cooler, as in boosted a little higher at the same temperature, in my Meshify C than my Define 7 Compact even with the same fans and fan configuration installed as scores in Cinebench 11, 20, and 23 are slightly better when using my Meshify C case. Still my main concern with why my 9800X3D starts to gradually throttle it's all-core frequency during CPU stress testing at 91C instead of staying at top boost frequency until its 95C Tjmax.

This morning I did some case fan cable management and disassembled the removeable top assembly of the case and during the process I noticed that I installed my rear exhaust fan backwards accidently, therefore it was intaking air instead of exhausting air which I believe was lowering the effectiveness my 2nd CPU fan exhausting heat from the CPU as they were both colliding air into each other. Therefore, I reinstalled that case fan as exhaust like it should be and now my 9800X3D seems to run slightly cooler now and takes longer to reach the Tjmax 95C and does not throttle as much as now Cinebench 11, 20, and 23 multicore scores slightly improved on my 9800X3D with the correct orientation of the rear exhaust case fan.

 

[LightningZ71]

"It's MegaMaid sir! She's gone from..."

Nope...
Not gonna do it...
Wouldn't be prudent...
At this junk-ture...


I'll see myself out now...

 

[DrMrLordX]

Not gonna do it...

Don't worry, someone else will.