Puppy has been tested on a few very old machines but the best results for the standard release of Puppy Linux to run at a reasonable pace have been achieved with the following:

CPU : Pentium 166MMX
RAM : 128 MB physical RAM for releases since version 1.0.2 or failing that a Linux swap file and/or swap partition is required for all included applications to run; 64 MB for releases previous to 1.0.2
Hard Drive : None
CDROM : 20x and up

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