Who moved my /3GB switch in boot.ini file?

Configuring the /3GB functionality using BCDEdit is not a difficult task.  You’ll need Administrator privileges, and an elevated command prompt.  The command itself is actually very simple:  BCDEDIT.EXE /Set IncreaseUserVa <value>.  <Value> in this command represents the number of megabytes that a user-mode process can use.  If you think of 1GB as 1024 MB (2^10) […]

Configuring the /3GB functionality using BCDEdit is not a difficult task.  You’ll need Administrator privileges, and an elevated command prompt.  The command itself is actually very simple:  BCDEDIT.EXE /Set IncreaseUserVa <value>.  <Value> in this command represents the number of megabytes that a user-mode process can use.  If you think of 1GB as 1024 MB (2^10) then to allow 3GB of memory we allot 3*1024 MB = 3072 MB.  Thus our command becomes BCDEDIT.EXE /Set IncreaseUserVa 3072.  We can tune this value as needed, just like we did when we combined /3GB and /USERVA in the boot.ini.  To set /3GB /USERVA=2970, we would BCDEDIT.EXE /Set IncreaseUserVa 2970.  Fairly straightforward, right?

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