I created a virtual machine with 128 MB and started to decrease it to check the minimal RAM requirement for XP to boot.
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64 MB - Boots normally, of course
![:P](http://www.x64bit.net/site/board/public/style_emoticons/default/tongue.png)
48 MB - Boots
![:rofl:](http://www.x64bit.net/site/board/public/style_emoticons/default/smile.png)
32 MB - Boots
![:lol:](http://www.x64bit.net/site/board/public/style_emoticons/default/smile.png)
16 MB - Error
![:D](http://www.x64bit.net/site/board/public/style_emoticons/default/sad.png)
20 MB - Error
![:(](http://www.x64bit.net/site/board/public/style_emoticons/default/sad.png)
21 MB - Error
![:(](http://www.x64bit.net/site/board/public/style_emoticons/default/sad.png)
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22 MB - Boots (Minimal requirement to run XP)
![:storm:](http://www.x64bit.net/site/board/public/style_emoticons/default/blink.png)
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