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: E-Core
In this batch of testing, we're focusing primarily on the E-cores. Intel claimed that the performance was around the level of its Skylake generation of processors (6th Gen to 10th Gen, depending which slide you read), and we had to put that to the test. In this instance, we're comparing to the flagship Skylake processor, the Core i7-6700K, which offered 4C/8T at 91 W. We also did a number of multi-threaded tests to see where the E-cores would line up.
In order to enable E-core only operation, we used affinity masks.
Single Threaded
In these few tests, we can see that the E-core is almost there at 4.2 GHz Skylake. Moving down to 3.9 GHz, perhaps something like the i7-6700, would put it on par.
Multi-Thread Tests
Having a full eight E-cores compared to Skylake's 4C/8T arrangement helps in a lot of scenarios that are compute limited. When we move to more memory limited environments, or with cross-talk, then the E-cores are a bit more limited due to the cache structure and the long core-to-core latencies. Even with DDR5 in tow, the E-cores can be marginal to the Skylake, for example in WinRAR which tends to benefit from cache and memory bandwidth.
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blanarahul - Thursday, November 4, 2021 - link
"Using all the eight E-cores, at 3.9 GHz, brings the package power up to 48 W total."This sounds amazing for inexpensive (i3 class) laptop processors since Gracemont sips power and doesn't take much die space.
Great_Scott - Thursday, November 4, 2021 - link
I'd actually prefer a all-Gracemont CPU for Laptops. Seems like it would be better for intentionally maximizing battery life. Skylake+ level performance is perfect for most use cases.TheinsanegamerN - Thursday, November 4, 2021 - link
Indeed, they have it backwards for laptops, it should be 2-6 gracemont cores then 1-2 power cores for a CPU, not the other way around.karmapop - Thursday, November 4, 2021 - link
I'm guessing you missed the articles describing the two separate mobile dies for Alder Lake? We've got Alder Lake-P (6P + 8E) for performance mobile designs, and Alder Lake-M (2P + 8E) for the ultra mobile low power SKUs.at_clucks - Saturday, November 6, 2021 - link
I'm very happy with exactly-Skylake-level performance in my desktop :). I'd more than gladly take the same performance and cut the power in half. I'm sure there's quite a big market for that kind of performance in a lower powered package regardless of form factor (mobile, desktop).Meteor2 - Tuesday, November 9, 2021 - link
There really is. I may well pick up a 2P+8E ADL laptop, but a desktop box would suit me bettermode_13h - Wednesday, November 10, 2021 - link
Keep an eye on ASRock. They sell mini-ITX motherboards with that class of SoC.https://www.asrock.com/mb/index.us.asp#Intel%20CPU
Spunjji - Friday, November 5, 2021 - link
That's actually not great in power terms compared to what AMD can do with 8 Zen 3 cores on TSMC N7 - but yeah, in the context of die area, something built around (say) 2 P cores and 4 E cores can probably put in a very good showing for inexpensive devices.Netmsm - Thursday, November 4, 2021 - link
Becomes competitive to previous AMD's.EnglishMike - Thursday, November 4, 2021 - link
Previous AMDs support DDR5 and PCR 5.0?Huh. That one slipped by me...