There is a lot of variation in PC’s support for the APM ( Advanced Power Management ) API.
Windows uses this to control the power saving features. If the notebook or PC does not support APM then power saving may be controlled through the BIOS setup. It looks like having a BIOS that only supports APM version 1.0 is bad news. If a computer is using APM 1.1 or later, the operating system can reject the request for suspend mode, with APM 1.0 it can not.
See Microsoft Knowledge Base article ID: Q119599 “Differences Between Using APM 1.0 and APM 1.1".
Some computers and BIOS revisions have known incompatibilities with the APM 1.1 specification.
See Microsoft Knowledge Base article ID: Q137402 “APM Features May Be Unavailable in Windows 95”
With some BIOS revisions the BIOS settings override the Windows APM timer settings. If the BIOS settings are less than the Windows timer settings make them greater. You may wish to upgrade the BIOS.
If you you are using MS DLC to communicate with the MSIU over a network, or if your network driver is an NDIS 2 driver then advanced power management may not work under Windows 95. Presumably the BIOS settings then take precedence.
16 bit MS DLC requires NDIS 2 drivers. With an NDIS2 driver installed Windows 95 rejects all APM requests because NDIS.VXD cannot know in what state the real-mode driver would resume upon resumption of power.
See knowledge base article ID: Q127872 "APM Does Not Function with NDIS 2 Adapter Driver"
This presumably also applies to Windows 98.
To configure power management use the Power Management control in the Control Panel.
Power Management can be disabled in the Device Manager of the System control in the Control Panel:
Double-click on System, and then select the Device Manager tab.
In the device tree click on + by the System devices branch to expand it.
Select Advanced Power Management in the device list and click on the Properties button ( or right click and select Properties from the pop-up menu ).
Select the General tab and disable in the Current hardware profile.
Exit and re-boot Windows.
Some Notebooks and PCs come with the manufacturers proprietary power management controls. These may be in the Control Panel, the Start Menu or the System Tray. They may take precedence over the Windows settings; please read the manufacturers documentation.
