Tip & How-To about Microsoft Windows XP Home Edition for PC

Mamimum RAM for User @ 3GB using boot.ini switch on 4GB Physical RAM

The DOS will always take a percentage of the physical RAM on the motherboard leaving the rest for the User. By default the Windows Operating System will use 50% of the physical RAM installed on the motherboard leaving the user the remaining 50% this can be changed using a switch in the boot.ini file

The /3GB was originally meant to be used in systems that have 3GB or more of RAM something that is no longer quite as rare as it used to be Windows XP SP3 will support upto 4GB although on a 32bit (x86) version of Windows will acually see 3.25gb that is the limitation.

However, even if you don't have 3 GB or more of memory, you can still use the /3GB switch. the switch can have any value between 2048 (2 GB) and 3072 (3 GB) megabytes. It needs to be expressed in decimal notation.

The /3GB switch applies to 32-bit systems only (x86).


Example with Windows XP SP3 Home Edition with the recovery console installed this gives you the option of default 50-50% split or the 3GB switch 75-25% split.

The /noexecute parameter enables, disables, and configures Data Execution Prevention (DEP), a set of hardware and software technologies designed to prevent harmful code from running in protected memory locations using the optin switch enables DEP only for operating system components, including the Windows kernel and drivers. Administrators can enable DEP on selected executable files by using the Application Compatibility Toolkit (ACT).

The /burnmemory parameter specifies the amount of memory, in megabytes, that Windows cannot use in this example, /burnmemory=128 will reduce the physical RAM memory that is available to Windows by 128 MB.

[boot loader]
timeout=10
default=multi(0)disk(0)rdisk(0)partition(1)WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)WINDOWS="Microsoft Windows XP Home Edition 3GB Switch" /noexecute=optin /3GB /fastdetect
multi(0)disk(0)rdisk(0)partition(1)WINDOWS="Microsoft Windows XP Home Edition " /noexecute=optin /burnmemory=128 /fastdetect
C:CMDCONSBOOTSECT.DAT="Microsoft Windows Recovery Console" /cmdcons


Check out the noexecute and the 3GB switch plus all available boot.ini switches HERE

I suggest that you use AnalogX MaxMem it is a realtime physical memory management program that automatically ensures that you always have as much physical memory available as possible used with the 3GB switch you should never have memory issues ever again.



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2 Answers

blue dump error 0x0000007b error coming


Try running the Check Disk Utility.

To run the check disk utility you will need a repair disc ora operating system disc. Put the disc in the cd drive and boot fromit. You want to get to the Dos Command Prompt (Black screen with whiteletters) and type the following command: chkdsk /r
Check disk will run well over an hour or two and you will notice thepercentages going from high to low, this is normal. Let it run tocompletion. Then reboot machine.

If check disk fails to solve your problem you might have to reinstall windows.Try doing a Repair Install that way you don't loose your data, documents,music, pictures, videos or programs.

In windows xp you get to the dos command prompt by selecting R for repair whenthe options appear.

In Vista and Windows 7 you want to get to the recoveryconsole and look down at the bottom of the window for the Dos Command.

Jun 02, 2012 | Computers & Internet

1 Answer

CMOS checksum error


Try running the Check Disk Utility.

To run the check disk utility you will need a repair disc ora operating system disc. Put the disc in the cd drive and boot fromit. You want to get to the Dos Command Prompt (Black screen with whiteletters) and type the following command: chkdsk /r
Check disk will run well over an hour or two and you will notice thepercentages going from high to low, this is normal. Let it run tocompletion. Then reboot machine.

If check disk fails to solve your problem you might have to reinstall windows.Try doing a Repair Install that way you don't loose your data, documents,music, pictures, videos or programs.

In windows xp you get to the dos command prompt by selecting R for repair whenthe options appear.

In Vista and Windows 7 you want to get to the recoveryconsole and look down at the bottom of the window for the Dos Command.

May 15, 2012 | Foxconn FC-G31MXP-K Motherboard

1 Answer

how to remove one operating system in dual boot?


-right click on my computer, select properties
-move to the advanced tab
-under 'startup and recovery' select settings
-in the new dialog box you have a couple of options:
-if you wish to leave DOS on the machine, but not see the option screen you can simply set the 'time to display list of operating systems:' to 0 as winXP should now be ur default OS
-if the removal of dos is your goal, then click edit
-first save a copy of the notepad file which opens 'boot.ini' just incase you make a mistake
-now there will be a lines similar to:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /NoExecute=OptIn

*There will also be a line for dos here under [operating systems] something like 'multi(1)disk(0)partition(#).....'
-check that your default line points to XP, as it does above
-now erase the line with the other OS, in this case DOS 7.1 ie. 'multi(1)' NOTE *the entire line may be more than one line in notepad*
-save the file
-then you are free to erase the folder associated with the erased OS NOTE *if a mistake was made, you may wish to do this as the last step*
-reboot your system and its done.

-upon any mistakes load into either DOS or XP, etc which ever is easiest (or still remaining on your system)
-copy the old boot.ini over the modified one, and try again
-good luck

Feb 01, 2011 | Computers & Internet

1 Answer

cannot see 4 gb ram


Hi Ciccio8670,

If you are running 32-bit Windows, you must live with it. You will not ever see all 4GB of RAM you've paid for.
If you are running 64-bit Windows, you may have to live with it. Depending on your motherboard's chipset, your system may support memory remapping. If so, you will be able to use all 4GB of RAM.

Detailed:
Due to an architectural decision made long ago, if you have 4GB of physical RAM installed, Windows is only able to report a portion of the physical 4GB of RAM (ranges from ~2.75GB to 3.5GB depending on the devices installed, motherboard's chipset & BIOS). This behavior is due to "memory mapped IO reservations". Those reservations overlay the physical address space and mask out those physical addresses so that they cannot be used for working memory. This is independent of the OS running on the machine. Significant chunks of address space below 4GB (the highest address accessible via 32-bit) get reserved for use by system hardware: • BIOS – including ACPI and legacy video support • PCI bus including bridges etc. • PCI Express support will reserve at least 256MB, up to 768MB depending on graphics card installed memory
What this means is a typical system may see between ~256MB and 1GB of address space below 4GB reserved for hardware use that the OS cannot access. Intel chipset specs are pretty good at explaining what address ranges gets reserved by default and in some cases call out that 1.5GB is always reserved and thus inaccessible to Windows.

Feb 13, 2008 | ASUS P4P800 SE (890552603657) Motherboard

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