Windows Cannot Hibernate Computer with More Than 4 GB Memory

4GB (4 gigabytes) has been a buzzword recently, mainly due to well publicize limit of maximum memory or RAM module supported and usable by 32-bit (x86) version of Windows Vista is 4 GB, especially in view of cheaper RAM stick price, enable user to purchase more memories to install onto their system. However, there is another limitation, or inconvenient for user using computer with more than 4 GB of memory, that is no hibernation feature support.

Microsoft confirms that user cannot put a computer that is running Windows XP, Windows Server 2003, Windows Vista, or Windows Server 2008 with more than 4 GB (gigabytes) of RAM (random access memory) installed into hibernation mode. This is not a bug but by design, as Microsoft disable hibernation support on PC with more than 4GB physical memory inserted because benchmark by Microsoft shows that performance is poor on a computer that has more than 4 GB of memory and that has support for hibernation, which requires sufficient disk space to contain the contents of the computer’s memory.

As such, user cannot find the Hibernate tab in the Power Options Properties dialog box, which is unavailable. Worse still, the issue affects both 32-bit and 64-bit versions of Windows XP, Windows Server 2003, Windows Vista and Windows Server 2008, although the x64 editions of Windows can support more than 4 GB of memory.

There is no resolution or solution to the hibernation turned off and not working issue. The only workaround is to reduce and decrease the RAM to 4 GB or less on the affected computer, which is unlikely to be done by most people.

And if you so love the hibernation feature that you remove some pieces of RAM module for it to fit Microsoft’s ‘requirement’ of 4GB internal memory or less, the Hibernation tab in Power Options may still not appearing. This issue occurs because Windows ‘remembers’ that it has more than 4 GB of memory as PCI memory resources are mapped in the middle of 4 GB physical memory address spaces, and the rest of the RAM is mapped to more than 4 GB of physical memory address space. If the value of the highest physical memory address is larger than 4 GB, Windows determines that the computer has more than 4 GB of memory.

To fix the Hibernation tab still not available or disabled after reducing memory amount to 4GB or less, add the /MAXMEM=4096 switch to placed at the end of the ARC path that is specified in the [operating systems] section of the Boot.ini file to reduce the highest physical memory to 4 GB for Windows XP, Server 2003 and Server 2008. For Windows Vista, enable hibernation by running “powercfg /h on” (without quotes) in an elevated command prompt.

More information at Microsoft KB888575.