[paulmd]

One other reason is that ECC is not binned for super high clocks like gaming RAM (even though there is nothing technically preventing it from doing so - it is one extra chip per stick, that's basically it). The fastest you can get is like 2666, where you can readily get gaming RAM in the 3600 range and premium bins go to 4400+.

Ryzen has always been very "sensitive" to low-clocked RAM and shows some pretty good scaling as you increase frequency and tighten timings and the ECC UDIMMs on the market are just not binned to do that.

[vbezhenar]

2666 is not the fastest ECC memory. Here's 3200 for example: https://www.newegg.com/crucial-32gb-288-pin-ddr4-sdram/p/N82...

[zrm]

That's registered memory, not supported by Ryzen/Threadripper. Find unregistered ECC DDR4 3200.

Or convince AMD to stop artificially not supporting registered memory on Ryzen/Threadripper -- the early Athlons supported both.

[paulmd]

I still am impressed though, didn't know about that one. Kinda trash CAS latency but I guess that might be because it's registered (I've never seen registered that fast so I guess I don't really have a good perspective on what "good CAS latency" would be for a registered memory).

I wonder if those would run on my Haswell-E xeons. They support RDIMMs, and they are unlocked so nominally they should support higher RAM clocks too (although I've never tried it with RDIMMs, only UDIMMs).

More recently, the W-3175X (Threadripper's real competitor) supports RDIMM as well. So Threadripper actually offers less features than the competition here.

I really would like to see the Threadripper series merged with the 7002P series though. Right now there is no option that gives you both Threadripper-level clocks and large quantities of RAM, the frequency-optimized parts are still a large compromise in performance and aren't widely supported. There is no part that gets you to 4 GHZ on 64 cores with 512+ GB of RAM, despite all of these capabilities existing in their respective segments.

When you are shipping a 64C HEDT processor there is really no longer any meaningful distinction between that and a server processor. And 256GB simply is not enough RAM for a 64C processor. AMD could still upcharge on the multi-socket models, but they are drawing lines between product segments that no longer make sense now that they have pushed core counts so high.

Basically, give us a modern successor to the Intel X5670 series. It's the top of the line, you're paying $4000 for a workstation processor, you should get the whole processor and not have a bunch of disabled features.

The really funny thing is, it's not even a money thing, Epyc isn't even priced significantly higher. 7702P is $4150 at Provantage (HPE p/n P16660-B21) vs $3990 for the 3990X. The 7402P (HPE p/n P16664-B21) is actually $250 cheaper than the 3960X. AMD is no longer using the "traditional" model where workstation is cheaper than server. Workstation is now just as expensive as server. So it's not like giving you Epyc capabilities would mean AMD foregoing any money.

AMD is just drawing arbitrary lines between these product segments because they can.

[zrm]

> I really would like to see the Threadripper series merged with the 7002P series though.

They should've done that when they changed the socket for the latest generation. Just admit that the existence of Socket TR4 was a mistake and release the new Threadrippers on Socket SP3.

I suspect there are even some people interested in dual socket workstations with 2TB of memory that nonetheless have a 4.5GHz boost clock, because workstations often have mixed workloads. And there is no point in doing market segmentation when all the prices are the same anyway, it's just incompatibility for no reason.

[greggyb]

Epycs should be readily overclockable. It's the same silicon as Threadripper. AMD does not, to my knowledge, restrict overclocking in server parts.

Cooling would become a big issue, though. Air cooling a 280W 3970X in a big tower with sufficient airflow to maintain ambient temperature internally is difficult. I cannot maintain max turbo on all cores.

Putting this in 1 or 2 Us in a server would likely be impossible without water cooling (requiring piping to external liquid coolers (whether radiators or chillers)). There's only so much that increasing air velocity can do in cooling.

I don't know if this is the primary thing holding back Epyc specs, but I know it will be an issue.