PC Building

[joumxyzptlk]

Currently running Rzyen 5950x (on ASRock x470 Taichi, 64 GB ECC RAM). The workloads I have make use of the 16 cores. The workloads would run faster with 3D Cache, but not this way.

I was hoping for the 7950X3D to have cache on both CCDs, and got disappointed. Now AMD disappoints me a second time. For the 7950X3D the explanation "thermal reason" seemed valid, but that cannot be the reason this time.

I will delay my PC upgrade again. Planned was: 9950X3D (with extra cache on BOTH CCDs) with 96 GB ECC RAM or 128 GB ECC RAM. But what for? Why not deliver the CPU the community is longing for? Why not listen to customers?

I feel mocked. My next computer will be AMD again, not only 'cause of real ECC RAM capabilities in consumer CPUs, but until then probably a new socket since the current will have reached its three or four generation limit and DDR6 will be there until then.

This "post new message" Form has a bug, the "PC Processors" list is EMPTY in Firefox: I cannot select the right "PC Processors" community, so it has to be in "Red PC Building", which is the closest. (Another disappointment, like Windows 11 24h2)

[BigAl01]

I used to be a component engineer back in the mid-1980's, working with vendors that were producing the highest quality semiconductor parts (S-level for space applications).  Thermal constraints have been an ongoing headache for the industry, even with process sizes getting smaller and smaller.  Todays processors were a pipe dream to the system engineers that were designing with 4-bit processors back then.  And here you are unhappy with the performance of the 7950X3D processor.  

Perhaps you need a workstation (Threadripper CPU?) that could better handle your workloads.

[johnnyenglish]

I think AMD already tested a 16core X3D and even though we are all curious, of course, if its not out yet its because its not viable. Either the chip itself or to be honest, the market.

The 9800X3D already has its way paved for dominance. Especially being capable of overclocking at insane levels where 7800X3D wouldn't even budge.

The thermal shouldn't be the issue as the 9800X3D is unlocked now.

Conclusion. 2 CCD with X3D will come, just not right now.

Also, getting a X3D CPU and use slow ECC memory doesnt add up. For true workloads the regular 7950X 170watt beast will just be plain better than the 7950X3D. Even older Threadrippers will still Kick the X3D model.

Just my 2cents

[joumxyzptlk]

> Also, getting a X3D CPU and use slow ECC memory doesnt add up.

actually the contrary: It does add up even more. The "slow" ECC memory is compensated by the larger cache. You already see the differences with normal overclocking RAM with and without cache. Make the RAM slower and the difference gets bigger.

I've been using ECC memory since Ryzen 2700x, and real ECC memory allows much better memory overclocking since you actually know when you hit the real limit, whereas without ECC you don't and have to rely on memory testing tools.

With ECC you get "Event id 47", "Microsoft-Windows-WHEA-Logger" "Recoverable Hardware Error" "Component Memory" followed by the bank, module number and address it happened in the XML data. Your machine gets slow since the CPU switches into a different mode, but does not crash, allowing a clean shutdown of programs and OS without corrupting data. This way I can test a memory speed over Months with various real workloads and actually KNOW it is a stable speed instead of guessing.

My current RAM originally specced as DDR4 2400 runs at 3066 with tight timings on the 5950x on that board (see profile info). With the 2700x I only got up to 2800, with 3900x to 2933, and still the same modules now at 3066 rock solid stable. Today I could even get DDR4 3200 ECC UDIMM which can be overclocked beyond 3600, possibly beyond 3800, but the speed gain would be too small.

ECC adds another advantage: If you think your PC is unstable, you actually KNOW if it is the RAM or not. You have the log in your OS. And EVERY current OS does log ECC errors. Windows (NT) and Linux even before the year 2000. Go back to older non-consumer OS-es and you will see it there too.

ECC is the one key feature of AMD consumer CPUs which makes Intel look laughable. You just have to select the right mainboard, but almost all support ECC now. It is a selling point.

[johnnyenglish]

Really liked your explanation and its true, mostly. But unfortunately its not that great of a deal for the average, thats why it said it doesn't add up, remember! I don't have your daily usage background and vast majority of x950X3D are either gamers or small time creators that make good use of a mix of CCDs.

I/We (at work), obviously use ECC memory in sensitive machines because its crucial to have it on a 24/7 machine or even a true worksation where time is money and downtime means a call to the IT guy to fix it (yours truly). However, at a consumer level like the x950X3D benefits are still niche and/or little to none.

I see you tried ECC memory for your workload, so did I (luckily I easy have access to it), but on my typical rendering & workload scenario for an hobby level Youtube video editing, benchmarks told me otherwise and its a complete gaming disaster. Even though I don't game that often as I used to. I'm sticking to a non 3DVCache 7950X for now.

If you run your PC for really extended periods of time, doing stuff, then there may be a need for ECC, but still.......... 

After I fine tuned my memory, I'm completely crash&error free for so long that i don't see the benefit of ECC for the average. And thats why AMD won't put out a consumer CPU like that.

Keep in mind it happened with HEDT non-PRO Threadripper, at some point i really though it was going away for good, but now its back. "Buyers" dictate if its worth putting out a product.

[johnnyenglish]

Some light about a full X3D

https://wccftech.com/amd-refutes-possibility-of-a-ryzen-x3d-cpu-having-3d-v-cache-on-all-ccds-citing... 

[BigAl01]

I can believe that.  Who wants to pay perhaps $1K for a CPU if it's intended for the consumer market?

[cpurpe91]

It would be rather silly to spend so much on a CPU when most workloads don't benefit from the 3D v-cache the way gaming does. My understanding has been that the 3D v-cache hinders performance in most workloads outside specific loads that are designed to use that extra cache.  

[joumxyzptlk]

Exactly. For my specific workloads it helps a lot. As example: AV1 encoding, since those GPU encoders give either good quality OR good size, but not both. Multithreaded via splitting, since the internal "tiling" multithreading hurts quality and size.

But having difference cache sizes make optimizing hard, and without the extra cache the speed increase is not good enough to make that CPU worth it.

[joumxyzptlk]

I do. It would not be the first 1000 € consumer CPU for me.

Still remember i7-4960x? Did cost 999€. Was worth it, I could use it. And is still in operation, albeit as Server with lots of storage and not main machine.

You opinion of what the CPU would be used for does not matter here, and it won't be used for what your immature comment suggests. I don't care about AI, and that would need a big GFX card, not a big CPU, so you are double off the mark.

Read my opening post: I can use my current 16 (32 with SMT) cores, done so for years. Those difference cache sizes would make it a lot more difficult to fully utilize the CPU. I recommend looking at a user profile before making a statement.

[joumxyzptlk]

Thanks for that link! In the end it says "not enough customers would buy it" "economic concerns". I hope they change their mind. I would buy it. The next step, a ZEN5 Threadripper or Epyc which matches 16 core with ~192 MB or more cache is a way too big financial step, both variants at least two times as expensive, probably closer to four times for everything. Result: I'll stick with my old Ryzen 5950 CPU for a bit longer. Maybe Intel will make a comeback and even offer ECC support for consumer CPUs.

[Vynski]

Did you ever consider the EPYC line of CPU's.  One of the features of the EPYC series is 3D cache.

[cpurpe91]

There are AM5 EPYC CPUs now if I am not mistaken.

[joumxyzptlk]

There are no ZEN5 AM5 epyc avail (yet). The biggest is 4584PX, ZEN4, with the same "only one CCD has 3d cache" limitation. But the hardware around that CPU is even more expensive.

[joumxyzptlk]

The only EPYC CPU with 16 Cures and the same or more cache than a 9950x3d would be AMD EPYC™ 9175F, https://www.amd.com/de/products/processors/server/epyc/9005-series/amd-epyc-9175f.html , Socket SP5, price (including tax) > 5000 €. To make use of that CPU it would need at least 4 * 32 GB ECC RAM , better 8 since it is optimized for interleave and not for highest RAM clock.

There are no ZEN5 Threadrippers out yet, but they won't be AM5 either. And at least 2000€ or more if I want more than the standard cache. The current Threadripper pro 7955WX does not have that extra cache as well, the 7960X has more cores than I need (well, maybe Windows 11 25h2 might change that...)

The 9950x3d with extra cache for both CCDs would fit my need perfectly.

[parapcc]

I can understand your frustration with the Ryzen 9950X3D not meeting your expectations regarding the 3D cache distribution across its CCDs. It's indeed disappointing when a highly anticipated product doesn't align with specific needs, especially for power users with specific performance requirements.