Specifying Amount of RAM Available to Windows Using MaxPhysPage

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Summary
This article contains a table of MaxPhysPage values you can use to limitthe amount of random access memory (RAM) available to Windows.
More information
To use the MaxPhysPage entry to specify the amount of RAM that isavailable to Windows, add the following line in the [386Enh] sectionof the System.ini file
   MaxPhysPage=<nnn>				

where <nnn> is a hexidecimal number that determines the number of memorypages available to Windows. A page is 4096 bytes of RAM for 486 andPentium processors.

When the MaxPhysPage entry is used, the following formula is used todetermine the amount of RAM available to Windows:
   4096 X MaxPhysPage (decimal) = Amount of RAM available to Windows in bytes				

Therefore, to limit Windows to 32 MB of memory, use the following formulato determine the MaxPhysPage entry:
   (32 * 1048576) / 4096 = 8192 (decimal) or 02000 (hexadecimal)				

NOTE: One megabyte is 1,048,576 bytes.

The following table list some common RAM amounts and the correspondingMaxPhysPage entry:
   Amount of RAM   available to Windows (MB)  (Bytes)           MaxPhysPage entry   --------------------------------------------------------------   960                        1,006,632,960     MaxPhysPage=3C000   896                          939,524,096     MaxPhysPage=38000   832                          872,415,323     MaxPhysPage=34000   768                          805,306,368     MaxPhysPage=30000   704                          738,197,504     MaxPhysPage=2C000   640                          671,088,640     MaxPhysPage=28000   576                          603,979,776     MaxPhysPage=24000   512                          536,870,912     MaxPhysPage=20000   448                          469,762,048     MaxPhysPage=1C000   384                          402,653,184     MaxPhysPage=18000   320                          335,544,320     MaxPhysPage=14000   256                          268,435,456     MaxPhysPage=10000   224                          234,881,024     MaxPhysPage=0E000   192                          201,326,592     MaxPhysPage=0C000   160                          167,772,160     MaxPhysPage=0A000   128                          134,217,728     MaxPhysPage=08000    96                          100,663,296     MaxPhysPage=06000    88                           92,274,688     MaxPhysPage=05800    80                           83,886,080     MaxPhysPage=05000    72                           75,497,472     MaxPhysPage=04800    64                           67,108,864     MaxPhysPage=04000    56                           58,720,256     MaxPhysPage=03800    48                           50,331,648     MaxPhysPage=03000    40                           41,943,040     MaxPhysPage=02800    32                           33,554,432     MaxPhysPage=02000    24                           25,165,824     MaxPhysPage=01800    16                           16,777,216     MaxPhysPage=01000    12                           12,582,912     MaxPhysPage=00C00    08                            8,388,608     MaxPhysPage=00800				

For additional information about MaxPhysPage, please see the followingArticles in the Microsoft Knowledge Base:
Article-ID: 134503
TITLE : Parity Error Messages May Indicate Bad Memory

Article-ID: Q83436 83436
Title : Windows 3.1 Resource Kit SYSTEM.INI [386ENH] Section M-Z
HWMEM how to
Properties

Article ID: 181862 - Last Review: 12/05/2015 08:26:31 - Revision: 4.0

Microsoft Windows 95

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