Intel BX80646I54570S Package C-States and Display Resolutions, Deepest Package C-State Available

Power Management—Processor

Note: Package C6 state is the deepest C-state supported on discrete graphics systems with PCI Express Graphics (PEG).

Package C7 state is the deepest C-state supported on integrated graphics systems (or switchable graphics systems during integrated graphics mode). However, in most configurations, package C6 will be more energy efficient than package C7 state. As a result, package C7 state residency is expected to be very low or zero in most scenarios where the display is enabled. Logic internal to the processor will determine whether package C6 or package C7 state is the most efficient. There is no need to make changes in BIOS or system software to prioritize package C6 state over package C7 state.

4.2.6Package C-States and Display Resolutions

The integrated graphics engine has the frame buffer located in system memory. When the display is updated, the graphics engine fetches display data from system memory. Different screen resolutions and refresh rates have different memory latency requirements. These requirements may limit the deepest Package C-state the processor can enter. Other elements that may affect the deepest Package C-state available are the following:

•Display is on or off

•Single or multiple displays

•Native or non-native resolution

•Panel Self Refresh (PSR) technology

Note: Display resolution is not the only factor influencing the deepest Package C-state the processor can get into. Device latencies, interrupt response latencies, and core C- states are among other factors that influence the final package C-state the processor can enter.

The following table lists display resolutions and deepest available package C-State. The display resolutions are examples using common values for blanking and pixel rate. Actual results will vary. The table shows the deepest possible Package C-state. System workload, system idle, and AC or DC power also affect the deepest possible Package C-state.

Table 20.	Deepest Package C-State Available
	Number of Displays 1	Native Resolution	Deepest Available Package C-
			State
	Single	800x600 60 Hz	PC6
	Single	1024x768 60 Hz	PC6
	Single	1280x1024 60 Hz	PC6
	Single	1920x1080 60 Hz	PC6
	Single	1920x1200 60 Hz	PC6
	Single	1920x1440 60 Hz	PC6
	Single	2048x1536 60 Hz	PC6
	Single	2560x1600 60 Hz	PC6
	Single	2560x1920 60 Hz	PC3
			continued...

Desktop 4th Generation Intel® Core™ Processor Family, Desktop Intel® Pentium® Processor Family, and Desktop Intel® Celeron® Processor Family

December 2013	Datasheet – Volume 1 of 2
Order No.: 328897-004	59