CPU rumors: Alder Lake-N with 8C at 7W, Lake Raptor with more cache

Photo: Intel

Alder Lake-N is an offshoot of the series for the combined region, but has nothing to do with the original. Since there are no large performance cores here, only small electronic cores instead. However, they should be used efficiently, Intel’s TDPs of 7W are for eight-core solutions with an iGPU.

Whether Alder Lake-N is still Intel Alder Lake at all is the number one question. Because without the large cores, it is no longer a hybrid design, but rather the solutions are now what previous Atom processors were: a certain number of small cores, along with the integrated graphics unit, marketed as Pentium and Celeron, among others.

Intel releases this in several variants, ranging from version 021, which represents 0 performance cores, 2 E cores and a GT1 graphics unit, to the 081 variant, i.e. still no performance cores, but eight efficiency cores and a GT1 graphics solution. Intel also puts a quad-core stack in the middle. Like the dual-core variant, it’s specified at 6 watts, and eight-core models are available at either 7 or 15 watts. Coreboot’s spec table reveals the first details, because the CPUs also have a turbo mode, then the 6-watt variants boost up to 25W, the 15W version up to the 35W PL2.

* VR Configurations for IA and GT domains for ADL-N SKU's.
 * Per doc#646929 ADL N Platform Design Guide -> Power_Map_Rev1p0
 *
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 * |      SKU       | Setting   | AC LL | DC LL | ICC MAX | TDC Current | TDC Time |
 * |                |           |(mOhms)|(mOhms)|   (A)   |     (A)     |   (msec) |
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 * | ADL-N 081(15W) |    IA     |  4.7  |  4.7  |    53   |      22     |  28000   |
 * +                +-----------+-------+-------+---------+-------------+----------+
 * |                |    GT     |  6.5  |  6.5  |    29   |      22     |  28000   |
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 * | ADL-N 081(7W)  |    IA     |  5.0  |  5.0  |    37   |      14     |  28000   |
 * +                +-----------+-------+-------+---------+-------------+----------+
 * |                |    GT     |  6.5  |  6.5  |    29   |      14     |  28000   |
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 * | ADL-N 041(6W)  |    IA     |  5.0  |  5.0  |    37   |      12     |  28000   |
 * +  Pentium       +-----------+-------+-------+---------+-------------+----------+
 * |                |    GT     |  6.5  |  6.5  |    29   |      12     |  28000   |
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 * | ADL-N 041(6W)  |    IA     |  5.0  |  5.0  |    37   |      12     |  28000   |
 * +  Celeron       +-----------+-------+-------+---------+-------------+----------+
 * |                |    GT     |  6.5  |  6.5  |    26   |      12     |  28000   |
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 * | ADL-N 021(6W)  |    IA     |  5.0  |  5.0  |    27   |      10     |  28000   |
 * +                +-----------+-------+-------+---------+-------------+----------+
 * |                |    GT     |  6.5  |  6.5  |    23   |      10     |  28000   |
 * +----------------+-----------+-------+-------+---------+-------------+----------+
 */

Raptor Lake brings more L2 and L3 cache

Intel is following the expected path with the successor to Alder Lake, Intel Raptor Lake. As in the server area, performance cores are now equipped with a 2MB cache per core, which is exactly what the Golden Cove cores used in Alder Lake already do in Sapphire Rapids, while in the consumer area it has been reduced to 1.25 MByte. Even with E cores, the full expansion of the maximum possible 4MB L2 cache for four cores hasn’t been used yet, but only 2MB per four cores. In the end, Intel was all over the place with Handbrake in Alder Lake, which makes mods for the update very easy.

Due to the architecture and structure of the hybrid chips, the L3 cache will also increase. Since the extra dual set of E-Cores, 16 instead of 8 cores, always brings an extra slice of 3MB L3 cache (LLC) for every 4 cores. All in all, Raptor Lake ends up with 36MB of L3 cache in its max configuration.

Intel Alder Lake as a group at a glance
Quick overview of Intel Alder Lake as a modular system (Photo: Intel)

Instead of 44MB, Alder Lake-S is now talking about 68MB cache, the maximum value that comes from simply adding 8×2MB L2 cache from P cores, plus 4×4MB from E cores and shared 36 MB L3 cache. The impact of variable caches will finally be felt in the second half of this year, when processors are introduced. Ultimately, of course, this is not possible without additional costs to Intel. Since the production in the 10nm alias “Intel 7” is identical, the CPU mold is inevitably larger. The Alder Lake-S large version has a footprint of 215 mm², dual E-Cores and modified caches throughout will allow the CPU to grow accordingly. Since it is still unknown what Intel will change, the approximate numerical value is still only a guess.

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