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AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

arstechnica.com

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Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#111

Post by [deleted] »

tom_alexander wrote: post #75
magicalhippo wrote: post #25

Probably fun for those who already bought DDR5 memory... still kicking myself for not just pulling the trigger on that 128GB dual stick kit I looked at for $600 back in September. Now it's listed at $4k... Meanwhile I hope my AM4 will chug along a few more years.

> Probably fun for those who already bought DDR5 memory Nah, those of us who already bought DDR5 memory also already bought decent CPUs. Dropping another $1k for these incremental gains would be silly. It'd make a lot more sense if DDR5 had been around longer so that people had the option to make generational upgrades to this CPU but DDR5 on AMD has only been around for Zen4 and Zen5.

[deleted]

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#112

Post by tyjen »

jofzar wrote: post #37
magicalhippo wrote: post #25

Probably fun for those who already bought DDR5 memory... still kicking myself for not just pulling the trigger on that 128GB dual stick kit I looked at for $600 back in September. Now it's listed at $4k... Meanwhile I hope my AM4 will chug along a few more years.

I really want a x3d because a game I play is heavily single threaded, I have the income and the financial stability but I can't in any good conscious upgrade to am5 with the ram prices. It's insane

I was waiting too, but the one game I play often that requires FPS performance decided to ruin their game with poor development direction. Now, I'm planning to buy for local llm hosting.

Here's hoping to more developments like TurboQuant to improve LLM memory efficiency.

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#114

Post by stingraycharles »

neRok wrote: post #86
stingraycharles wrote: post #35

Earlier quoted context omitted.

I think it’s mostly that they had leftover cache.

This video made the argument that AMD released it to not give Intel a look-in: [AMD KILLED Intel's 290K Dreams w/ R9 9950X3D2]( https://www.youtube.com/watch?v=u7SyrDPbKls )

I like this theory more, perhaps it’s both.

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#116

Post by WD-42 »

2001zhaozhao wrote: post #69
sspiff wrote: post #62

Earlier quoted context omitted.

I bought 192GB (4x 48GB) of DDR5-6400 for 299 euro in September but returned it because I couldn't get 4 DIMMS to run at decent speeds in the system. 6 or so weeks after I returned it the kit was listed at 1499.

Yeah the only way to run 4 sticks of DDR5 decently is with Intel. It's a bit of a shame that you can't cram enough RAM to run big models. The most I could get running on 10GB VRAM + 96GB RAM was a REAP'd + quantized version of MiniMax-M2.5

I’m running 128gb on a 9550x now with 4x32gb sticks and it’s terrible. It’s unstsable, post time is about 2 minutes (not exaggerating)and I’m stuck at a lower speed. I’m considering just taking 2 of the sticks out and working with 64gb and increasing my swap partition. The nvme drive is fast at least.

This is my first time off intel and I have to say I don’t understand the hype.

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#117

Post by Aurornis »

adrian_b wrote: post #81
Aurornis wrote: post #43

Earlier quoted context omitted.

> Now it's listed at $4k... You can buy 128GB of DDR5-6000 with a 9950X3D (not this newest X2 version, but still a $699 CPU) and a motherboard and a case for $2800 right now: https://www.newegg.com/Product/ComboDealDetails?ItemList=Com... If you don't need 128GB, there are quality 64GB kits for under $700 on Newegg right now, which is cheaper than this CPU. If someone needs to build something now and can wait to upgr…

$2800 is still a huge price in comparison with the last year. Last summer, a 9950X3D + motherboard + cooler + 128 GB DRAM + VAT sales taxes was the equivalent of $1400 in Europe, where I live. That's half of your quoted price. That was without case and PSU, but adding e.g. $200 for those would not change much.

Yes of course. We all know prices are up.

I commented because someone thought that $4K was the going price for 128GB of RAM, which is way too much even with the demand crunch.

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#118

Post by nicman23 »

Aurornis wrote: post #43
magicalhippo wrote: post #25

Probably fun for those who already bought DDR5 memory... still kicking myself for not just pulling the trigger on that 128GB dual stick kit I looked at for $600 back in September. Now it's listed at $4k... Meanwhile I hope my AM4 will chug along a few more years.

> Now it's listed at $4k... You can buy 128GB of DDR5-6000 with a 9950X3D (not this newest X2 version, but still a $699 CPU) and a motherboard and a case for $2800 right now: https://www.newegg.com/Product/ComboDealDetails?ItemList=Com... If you don't need 128GB, there are quality 64GB kits for under $700 on Newegg right now, which is cheaper than this CPU. If someone needs to build something now and can wait to upgr…

that bs of you don't need 128 are toxic. what if you want to upgrade from ddr4 and you already have 128?

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#119

Post by Aurornis »

throwup238 wrote: post #106
Aurornis wrote: post #49

Earlier quoted context omitted.

> Absolute cheapest DDR5 128GB kit around is 2 sticks of 5600 64GB for $2k. That's not far from the bundle deal above, once you subtract the $700 CPU. If you really need 128GB the 5600 kit is fine. Having 208MB of total cache on the CPU means the real world difference between a 5600 kit and a slightly faster kit is negligible in most use cases. If you don't need to upgrade then clearly don't force an upgrade right no…

> a slightly faster kit is negligible in most use cases Does that “most use cases” caveat really apply to someone buying 128G of RAM? If I’m buying that much, it means I’m actually going to put it through its paces, unless it’s just there for huge reserved guest VM overhead.

The 208MB of total cache on the CPU we’re discussing does a good job of reducing sensitivity to RAM speed differences on this platform.

If you’re trying to run LLMs off of the CPU instead of the GPU then the RAM speed dictates a lot. It’s going to be slow mo matter what, though. Dual channel DDR5 just isn’t enough to run large LLMs that start to fill 128GB of RAM and the difference between 5600 and 6400 isn’t going to make it usable.

If you’re just running a lot of VMs or doing a lot of mixed tasks that keep a lot of RAM occupied then you’d probably have a hard time measuring a difference between 5600 and 6400 if you tried with one of these X3D CPUs with a lot of cache.

This is a frequent topic of discussion for gamers because some people obsess over optimizing their RAM speed and timings and pay large premiums for RAM with CAS latency of 28 instead of 36. Then they see benchmarks showing 1-2% differences in games or even most productivity apps and realize they would have been better spending that extra money on the next faster GPU or CPU or other part.

Re: AMD's Ryzen 9 9950X3D2 Dual Edition crams 208MB of cache into a single chip

#120

Post by Aurornis »

monster_truck wrote: post #91
Aurornis wrote: post #40

Earlier quoted context omitted.

> The extra cache doesn't do a damn thing (maybe +2%) It depends on the task. For some memory-bound tasks the extra cache is very helpful. For CFD and other simulation workloads the benefits are huge. For other tasks it doesn't help at all. If someone wants a simple gaming CPU or general purpose CPU they don't need to spend the money for this. They don't need the 16-core CPU at all. The 9850X3D is a better buy for mo…

It really doesn't. In virtually every case the work is being completed faster than the cache can grow to that size. What little gains are being realized are from not having to wait for cores with access to the cache to become available.

> It really doesn't. In virtually every case the work is being completed faster than the cache can grow to that size.

If your tasks don’t benefit then don’t buy it.

But stop claiming that it doesn’t help anywhere because that’s simply wrong. I do some FEA work occasionally and the extra cache is a HUGE help.

There are also a lot of non-LLM AI workloads that have models in the size range than fit into this cache.

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