There are a number of sleep states for Win 8/10...
System Sleep States
In this post, we will see the different System Sleep States in Windows.
MSDN explains this quite well.
System Power State S0 – This is the Working State, where your Windows PC is awake. This is not a Sleep state.
System Power State S1 – In this sleep state, the CPU is stopped and your computer is in standby mode. If the next S3 state is note supported, this S2 is the default state on most hardware. The Processor clock is off and bus clocks are stopped. In this state, the power consumption could be between 5 – 30 Watts.
System Power State S2 – This state is similar to S1 except that the CPU context and contents of the system cache are lost because the processor loses power.
System Power State S3 – In this state, data or context is saved to RAM and hard drives, fans, etc. are shut down. The power consumption is usually less than 5 Watts.
Wake-On-LAN is supported from S3 (Sleep) or S4 (Hibernate) state in Windows 10/8.
System Power State S4 – In this state, data or context is saved to Disk. It is also known as the
Hibernate state and is useful for laptops. Your PC saves the contents of RAM to the hard disk. The hardware powers off all devices. Operating system context, however, is maintained in a hibernate file that the system writes to disk before entering the S4 state. Upon restart, the loader reads this file and jumps to the system’s previous, pre-hibernation location. Power consumption is again less than 5 Watts.
http://www.thewindowsclub.com/system-sleep-states-windows-8