Alder Lake (microprocessor)
Alder Lake is Intel's codename for the 12th generation of Intel Core processors based on a hybrid architecture utilizing Golden Cove high-performance cores and Gracemont power-efficient cores.  It is fabricated using Intel's Intel 7 process, previously referred to as Intel 10 nm Enhanced SuperFin (10ESF). Intel officially announced 12th Gen Intel Core CPUs on October 27, 2021. Intel officially announced 12th Gen Intel Core mobile CPUs and non-K series desktop CPUs on January 4, 2022. Intel officially announced the launch of Alder Lake-P and -U series on February 23, 2022.

Features

CPU

 Golden Cove high-performance "Performance-cores" (P-cores)
 Dedicated floating-point adders
 New 6-wide instruction decoder (up from 4-wide in Rocket Lake/Tiger Lake) with the ability to fetch up to 32 bytes of instructions per cycle (up from 16)
 12 execution ports (up from 10)
 512 reorder-buffer entries (up from 384)
 6-wide μOP allocations (up from 5)
 μOP cache size increased to 4K entries (up from 2.25K)
 AVX-VNNI, a VEX-coded variant of AVX512-VNNI for 256-bit vectors
 AVX-512 (including FP16) is present but disabled by default to match E-cores. It still can be enabled on some motherboards with some BIOS versions by disabling the E-cores 
 ~18% IPC uplift.
 Gracemont high-efficiency "Efficient-cores" (E-cores)
 E-cores are organized in 4-core modules; L2 cache is shared between E-cores within a module
 256 reorder-buffer entries (up from 208 in Tremont)
 17 execution ports (up from 12)
 AVX2, FMA and AVX-VNNI to catch up with P-cores
 Skylake-like IPC.
 new instruction set extensions
 up to 1 TB/s interconnect between cores 
 Intel Thread Director, which is a marketing name for Enhanced Hardware Feedback Interface (EHFI). This is a hardware technology to assist the OS thread scheduler with more efficient load distribution between heterogeneous CPU cores. Enabling this new capability requires support in an operating system.
 up to 30 MB L3 cache
 nomenclature:
 up to 8 P-cores and 8 E-cores on desktop
 up to 6 P-cores and 8 E-cores on mobile (UP3 designs)
 up to 2 P-cores and 8 E-cores on ultra mobile (UP4 designs)
 only P-cores feature Hyper-threading

GPU
 Intel Xe (Gen12.2) GPU
 up to 96 EU on mobile and 32 EU on desktop

I/O
 LGA 1700 socket for desktop processors
 BGA Type3 and Type4 HDI for mobile processors
 20 PCIe lanes from CPU
 16 PCIe 5.0 lanes
 4 PCIe 4.0 lanes
 Chipset link - DMI 4.0 x8 link with Intel 600 series PCH chipsets
 DDR5, DDR4, LPDDR5, and LPDDR4 memory support
 up to DDR4-3200
 up to DDR5-4800
 XMP 3.0
 Dynamic Memory Boost
 Integrated Thunderbolt 4 and WiFi 6E support

Dies 
For the Alder Lake generation, Intel will initially produce 4 different dies. Each die has a different number of P-cores (P) and E-cores (E) and GPU Execution Units.

Software support 

Alder Lake requires special support from the operating system due to its relatively unusual-for-x86 hybrid nature. For software unable to be upgraded, a UEFI-provided compatibility mode may be used to disable the E cores; it is enabled by the user turning on scroll lock.

CPUID incoherence 
The P and E cores of Alder Lake CPUs report different CPUID models. As a result, this may cause issues with digital rights management systems that perceive the P and E cores as being separate computers, and falsely enforce license restrictions preventing a particular piece of software from being executed on more than one device at a time. Intel published a list of PC games it identified as having this compatibility issue, and stated that it was working with publishers to develop patches. Some of the games were identified by Intel as only having this bug on Windows 10, and functioning correctly on Windows 11 (with some of them dependent on Windows 11 patches scheduled to be released in November 2021).

The Intel Game Dev Guide for Alder Lake also cautions against the use of undefined behavior in bitwise operations, as the two cores can act differently.

Scheduler support 
Alder Lake's CPU topology has performance implications, especially for gaming environments where the developers are not used to NUMA setups. Microsoft added support for Intel Thread Director (ITD) in Windows 11. A wide variety of inputs, including whether a process' window is in the foreground, feeds into the ITD. The ITD can function to a lesser extent with the OS providing less or no cooperation. Support in Linux is merged in kernel 5.18 but this alone is not sufficient until the kernel gets hints from userspace in order to schedule tasks to run on certain types of cores.

Blu-Ray DRM support 
The CPU family no longer features Intel SGX which is a requirement for playing UltraHD Blu-Ray disks.

List of 12th generation Alder Lake processors

Desktop processors (Alder Lake-S) 

 All the CPUs support up to 128 GB of DDR4-3200 or DDR5-4800 RAM in dual channel mode.
 Some models feature integrated UHD Graphics 770, UHD Graphics 730 or UHD Graphics 710 GPU with 32/24/16 EUs and base frequency of 300 MHz.
 By default Alder Lake CPUs are configured to run at Turbo Power at all times and Base Power is only guaranteed when P-Cores/E-cores do not exceed the base clock rate.
Max Turbo Power: the maximum sustained (> 1 s) power dissipation of the processor as limited by current and/or temperature controls. Instantaneous power may exceed Maximum Turbo Power for short durations (≤ 10 ms). Maximum Turbo Power is configurable by system vendor and can be system specific.

Mobile processors

Alder Lake-H

Alder Lake-P

Alder Lake-U

See also
Intel Core
Intel Lakefield
Sapphire Rapids, a codename for Intel's next generation Xeon server processors based on Intel 7

References

Intel x86 microprocessors