Vista system sleep menu disappears? Can't implement hibernation?

Description of the problem In Windows Vista, use the “Hibernate” function to standby, but found that the “Start” menu does not provide the “Hibernate” option in the menu. “Close Windows” The dialog box also did not find the "Hibernate" option?

Cause Analysis 1. The hibernation file cleanup program has been removed using the Disk Cleanup utility. 2. The computer does not support the sleep function. 3. The sleep function is disabled. 4, enabled the "mixed sleep" function. When the user selects the “sleep” option in any of the power options menus, the “Mixed Sleep” function puts the computer to sleep and generates a hibernation file. Therefore, if “Hybrid Sleep" is enabled, &"hibernation> will not appear as a power option. First, how can we know that our computer does not support the sleep function? 1. Click “Start”, find “command prompt" in the "Accessories", right click on “command prompt”, then click “run as administrator”. (If you are prompted for an administrator password or for confirmation, type the password or click “Continue .) 2. At the command prompt, type powercfg /a to display the unit for sleep, hibernation, mixing Support for sleep. Second, if the computer can support the hibernation function, how can it be enabled? You can use the PowerCfg command line tool to enable hibernation. To do this, follow the steps below. 1. Click “Start”, find “command prompt> in the "attachments", right click on “command prompt”, then click “run as administrator”. (If you are prompted for an administrator password or for confirmation, type your password or click “Continue . 2. At the command prompt, type powercfg /hibernate on. You can re-enable hibernation.