What should I do if Windows 7 cannot "sleep" properly?

Symptom: Since upgrading from xp to windows7, the notebook cannot be used normally. "Sleep" function, after using the sleep function, it can wake up, but the screen is black, you can't see it, and it is still the same after reinstalling the system. How to solve this problem?
Solution:
1, some motherboards need to enable sleep support function in bios, you can see in the "Device Manager" "System Device" There is no option called "acpi-compliant system", otherwise it is not a prerequisite for sleep and needs to be enabled in bios.
2, In addition, to ensure the correct installation or upgrade of all current hardware compatible windows7 drivers, such as wireless network card driver, Bluetooth driver, etc.; when not using the system, close the unconnected Bluetooth, unconnected wireless network, etc. Match and open hardware.
Expand “Computer”→“Manage ”→“Device Manager”, then right click on <;properties" on the network card and other devices, and "Allow this device to wake the computer" The front hook is removed, and the power management status is checked through the powercfg command line (“start”→“program”→“accessory”→“command prompt”→type“ Powercfg-a”).