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Memory Power Savings Technologies - 005 - ID:655258 | Core™ Processors (intel.com)
Divided into three parts:
Memory Power Savings Technologies
Display Power Savings Technologies
Processor Graphics Core Power Savings Technologies
Memory Power Savings Technologies
memory power saving technology
Intel® Rapid Memory Power Management (Intel® RMPM)
Intel® Rapid Memory Power Management (Intel® RMPM) conditionally places memory into self-refresh when the processor is in package C3 or deeper power state to allow the system to remain in the deeper power states longer for memory not reserved for graphics memory. Intel® RMPM functionality depends on graphics/display state (relevant only when processor graphics is being used), as well as memory traffic patterns generated by other connected I/O devices.
Display Power Savings Technologies
Display-controlled power-saving technology
Intel® Seamless Display Refresh Rate Switching Technology (Intel® SDRRS Technology) with eDP* Port
Intel® DRRS provides a mechanism where the monitor is placed in a slower refresh rate (the rate at which the display is updated). The system is smart enough to know that the user is not displaying either 3D or media like a movie where specific refresh rates are required. The technology is very useful in an environment such as a plane where the user is in battery mode doing E-mail, or other standard office applications. It is also useful where the user may be viewing web pages or social media sites while in battery mode.
Intel® Automatic Display Brightness
Automatically adjust backlight technology.
Intel® Automatic Display Brightness feature dynamically adjusts the back-light brightness based upon the current ambient light environment. This feature requires an additional sensor to be on the panel front. The sensor receives the changing ambient light conditions and sends the interrupts to the Intel Graphics driver. As per the change in Lux, (current ambient light luminance), the new back-light setting can be adjusted through BLC (Back Light Control). The converse applies for a brightly lit environment. Intel® Automatic Display Brightness increases the back-light setting.
Smooth Brightness
Smooth Brightness Adjustment
The Smooth Brightness feature is the ability to make fine grained changes to the screen brightness. All Windows* 10\11 system that support brightness control are required to support Smooth Brightness control and it should be supporting 101 levels of brightness control. Apart from the Graphics driver changes, there may be few System BIOS changes required to make this feature functional.
Intel® Display Power Saving Technology (Intel® DPST) 7.0
The Intel® DPST technique achieves back-light power savings while maintaining a good visual experience. This is accomplished by adaptively enhancing the displayed image while decreasing the back-light brightness simultaneously. The goal of this technique is to provide equivalent end-user-perceived image quality at a decreased back-light power level.
Enhances the picture being displayed while reducing the brightness of the backlight.
The original (input) image produced by the operating system or application is analyzed by the Intel® DPST subsystem. An interrupt to Intel® DPST software is generated whenever a meaningful change in the image attributes is detected. (A meaningful change is when the Intel® DPST software algorithm determines that enough brightness, contrast, or color change has occurred to the displaying images that the image enhancement and back-light control needs to be altered.)
The original image generated by the operating system or application is analyzed by intel's DPST subsystem. The DPST software algorithm changes the brightness, contrast, and color of the image.
Intel® DPST subsystem applies an image-specific enhancement to increase image contrast, brightness, and other attributes.
A corresponding decrease to the back-light brightness is applied simultaneously to produce an image with similar user-perceived quality (such as brightness) as the original image.
Intel® DPST 7.0 has improved power savings without adversely affecting the performance.
Panel Self-Refresh 2 (PSR 2)
Panel Self-Refresh feature allows the Processor Graphics core to enter low-power state when the frame buffer content is not changing constantly. This feature is available on panels capable of supporting Panel Self-Refresh. Apart from being able to support, the eDP* panel should be eDP 1.4 compliant. PSR 2 adds partial frame updates and requires an eDP 1.4 compliant panel.
Low-Power Single Pipe (LPSP)
Low-power single pipe is a power conservation feature that helps save power by keeping the inactive pipes powered OFF. This feature is enabled only in a single display configuration without any scaling functionalities. This feature is supported from 4th Generation Intel® Core™ processor family onwards. LPSP is achieved by keeping a single pipe enabled during eDP* only with minimal display pipeline support. This feature is panel independent and works with any eDP panel (port A) in single display mode.
Intel® Smart 2D Display Technology (Intel® S2DDT)
Intel® S2DDT reduces display refresh memory traffic by reducing memory reads required for display refresh. Power consumption is reduced by less accesses to the IMC. Intel S2DDT is only enabled in single pipe mode.
Intel® S2DDT is most effective with:
Display images well suited to compression, such as text windows, slide shows, and so on. Poor examples are 3D games.
Static screens such as screens with significant portions of the background showing 2D applications, processor benchmarks, and so on, or conditions when the processor is idle. Poor examples are full-screen 3D games and benchmarks that flip the display image at or near display refresh rates.
Processor Graphics Core Power Savings Technologies
Graphics processor power saving technology
Intel® Graphics Dynamic Frequency
Intel® Turbo Boost Technology 2.0 is the ability of the processor IA cores and graphics (Graphics Dynamic Frequency) cores to opportunistically increase frequency and/or voltage above the guaranteed processor and graphics frequency for the given part. Intel® Graphics Dynamic Frequency is a performance feature that makes use of unused package power and thermals to increase application performance. The increase in frequency is determined by how much power and thermal budget is available in the package, and the application demand for additional processor or graphics performance. The processor IA core control is maintained by an embedded controller. The graphics driver dynamically adjusts between P-States to maintain optimal performance, power, and thermals. The graphics driver will always place the graphics engine in its lowest possible P-State. Intel® Graphics Dynamic Frequency requires BIOS support. Additional power and thermal budget should be available.
Dynamic increase of core frequency or voltage
Intel® Graphics Render Standby Technology (Intel® GRST)
Intel® Graphics Render Standby Technology is a technique designed to optimize the average power of the graphics part. The Graphics Render engine will be put in a sleep state, or Render Standby (RS), during times of inactivity or basic video modes. While in Render Standby state, the graphics part will place the VR (Voltage Regulator) into a low voltage state. Hardware will save the render context to the allocated context buffer when entering RS state and restore the render context upon exiting RS state.
Renderer dynamic sleep technology
Dynamic FPS (DFPS)
Dynamic FPS (DFPS) or dynamic frame-rate control is a runtime feature for improving power-efficiency for 3D workloads. Its purpose is to limit the frame-rate of full screen 3D applications without compromising on user experience. By limiting the frame rate, the load on the graphics engine is reduced, giving an opportunity to run the Processor Graphics at lower speeds, resulting in power savings. This feature works in both AC/DC modes.
Dynamic frame rate adjustment