"After October 22, 2010, you’ll no longer be able to buy new PCs with Windows XP installed."
 
Apart from saying good bye to a venerable operating system that was released for retail sale on October 25, 2001, you must note that this is the end of machines with little memory, since the successor is much memory hungry. Windows XP minimal requirements were a 32-bit processor - say an Intel Pentium at 100 MHz - and 32 Mbyte RAM for memory. Windows 7 minimal requirements are a processor at 1000 MHz and 1024/2048 Mbyte RAM.
 
 
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