From: nowhere@never.at   
      
   On 20.07.2021 19:56, James Harris wrote:   
   ...   
   >>>> All modern PC's start with A20 enabled.   
      
   >>> Er, how are you defining "modern"?   
      
   >> all my machines don't even have an A20 gate anymore, since 2010.   
      
   > All your machines are chosen to be of the same kind, aren't they? IIRC   
   > you were buying and selling machines which were specifically intended to   
   > be the same as each other so you could rely on their hardware being   
   > compatible.   
      
   yes all from one vendor but different generations 2010/2014/2018.   
   there were a few software things to modify for a hardware change.   
      
   >> but I kept the few bytes to check ffff:0010 isn't equal to 0:0.   
   > Very sensible. It's virtually cost-free assurance.   
      
   it was cheaper to keep it :)   
    push -1   
    pop es          I need this four anyway   
    push 0          done during boot once   
    pop ds   
   66 A1 00 00       mov eax,[0000]   
   36 66 3B 06 10 00 cmp eax,[es:0010]   
   74 xx             JZ ... ;A20 failed   
   __   
   wolfgang   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)