The Intel 12th Gen Core i9-12900K Review: Hybrid Performance Brings Hybrid Complexity
by Dr. Ian Cutress & Andrei Frumusanu on November 4, 2021 9:00 AM ESTCPU Benchmark Performance: DDR5 vs DDR4
Traditionally we test our memory settings at JEDEC specifications. JEDEC is the standards body that determines the requirements for each memory standard. In this case, the Core i9 supports the following aligning with those standards:
- DDR4-3200 CL22
- DDR5-4800B CL40*
There's an * next to the DDR5 for a couple of reasons. First, when asked, Intel stated that 4800A (CL34) was the official support, however since the technical documents have now been released, we've discovered that it is 4800B (CL40). Secondly, 4800B CL40 technically only applies to 1 module per 64-bit channel on the motherboard, and only when the motherboard has two 64-bit slots to begin with. We covered Intel's memory support variants in a previous article, and in this instance, we're using DDR5-4800B memory in our testing.
As explained in our SPEC section, DDR5 memory not only brings bandwidth improvements but also the increased number of channels (4x32-bit vs 2x64-bit) means that the memory can be better utilized as threads pile on the memory requests. So while we don't see much improvement in single threaded workloads, there are a number of multi-threaded workloads that would love the increased performance.
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Kvaern1 - Sunday, November 7, 2021 - link
Because there are no games which are 'incompatible'' with ADL.eastcoast_pete - Sunday, November 7, 2021 - link
While AL is an interesting CPU (regardless of what one's preference is), I still think the star of AL is the Gracemont core (E cores), and did some very simple-minded, back of a napkin calculations. The top AL has 8 (P cores with multithreading) = 16 + 8 E core threads (no multithreading here) for a total of 24 threads. According to first die shots, one P core requires the same die area as 4 E cores. That leaves me wanting an all-E core CPU with the same die size as the i9 AL, because that could fit 8x4= 32 plus the existing 8 Gracemonts, for a total of 40. And, the old problem of "Atoms can't do AVX and AVX2" is solved - because now they can! Yes, single thread performance would be significantly lower, but any workload that can take advantage of many threads should be at least as fast as on the i9. Anyone here knows if Intel is considering that? It wouldn't be the choice for gaming, but for productivity, it might give both the i9 and, possibly, the 5950x a run for the money.mode_13h - Monday, November 8, 2021 - link
They currently make Atom-branded embedded server CPUs with up to 24 cores. This one launched last year, using Tremont cores:https://ark.intel.com/content/www/us/en/ark/produc...
I think you can expect to see a Gracemont-based refresh, possibly with some new product lines expanding into non-embedded markets.
eastcoast_pete - Monday, November 8, 2021 - link
Yes, those Tremont-based CPUs are intended/sold for 5G cell stations; I hope that Intel doesn't just refresh those with Gracemont, but makes a 32-40 Gracemont core CPU available for workstations and servers. The one thing that might prevent that is fear (Intel's) of cannibalizing their Sapphire Rapid sales. However, if I would be in their shoes, I'd worry more about upcoming AMD and multi-core ARM server chips, and sell all the CPUs they can.mode_13h - Tuesday, November 9, 2021 - link
Well, it's a start that Intel is already using these cores in *some* kind of server CPU, no? That suggests they already should have some server-grade RAS features built-in. So, it should be a fairly small step to use them in a high core count CPU to counter the Gravitons and Altras. I think they will, since it should be more competitive in terms of perf/W.As for workstations, I think you'll need to find a workstation board with a server CPU socket. I doubt they'll be pushing massive E-core -only CPUs specifically for workstations, since workstation users also tend to care about single-thread performance.
anemusek - Sunday, November 7, 2021 - link
Sorry but performance it isn't all +- a few percent in the real world will not restore confidence. Critical flaws, disabling functionality (dx12 in hanswell for example), instabbility instruction features etc.I cannot afford to trust such a company
Dolda2000 - Sunday, November 7, 2021 - link
I just wanted to add a big Kudos for this article. AnandTech's coverage of the 12900K was by a wide margin the best of any I read or watched, with regards to coverage of the various variables involved, and with the breadth and depth of testing. Thanks for keeping it up!chantzeleong - Monday, November 8, 2021 - link
I run Power bi and tensorflow with large dataset. Which Intel CPU do you recommend and why?mode_13h - Tuesday, November 9, 2021 - link
I don't know about "Power bi", but Tensorflow should run best on GPUs. Which CPU to get then depends on how many GPUs you're going to use. If >= 3, then Threadripper. Otherwise, go for Alder Lake or Ryzen 5000 series.You'll probably find the best advice among user communities for those specific apps.
velanapontinha - Monday, November 8, 2021 - link
We've seen this before. It is time to short AMD, unfortunately.