Puppy is ODD -- it is built from scratch by a crew of Australians and New Zealanders that used to be led by Barry Krauler before he retired yet again.
They all had obsolete machines (and I mean DOS level old machines). They wrote a crop of Puppies that would fit their machines.
I looked at the site yesterday and there is still a whole litter of puppies over there of all sorts and descriptions. One of these was an Ubuntu Puppy, but it was noted as as being a porky puppy.
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More organized Ubuntu based (for very old machines) alternativeshttp://lubuntu.net/Lubuntu is one of the skinniest semi-official Ubuntus out there. It will fit your machine's specs but you have to have PAE on your machine. It is LXDE based as are all of the very light distros.
This Ubuntu based distro is so far off from normal Ubuntu function-wise it got cut loose by the main group to become an independent spin as NOTHING MUCH IS LEFT UNALTERED in order to get Lubuntu that durn small. But the documentation is very well done since at one time it was an Official Ubuntu distro, just the very skinniest of them.
Lubuntu is your "good shot" at a semi-official Ubuntu that will fit your machine -- be aware that the supporting group is now very small like the distro is small, but all the stuff on the web site certainly remembers being an officially supported branch of Ubuntu.
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Peppermint is another independent LXDE spin of Linux Mint/Ubuntu that can run very light on resources. One of its main tricks is to get you on the web then use somebody else's server power to do most of your heavy lifting. Because of this trick Peppermint can do a lot your machine by itself really can't possibly do, but once again it goes far far far away from the standard distro it came from in how it utilizes exterior server power for extra speed and processing power in normal functions.
http://peppermintos.com/about/System Requirements for Peppermint Four
Here's what you'll need to run this distro:
Absolute Minimum:
192 MB of RAM
Processor based on Intel x86 architecture
At least 2 GB of available disk space
Recommended Minimum:
512 MB of RAM
Processor based on Intel x86 architecture
At least 4 GB of available disk spaceHowever, Peppermint always struck me as being well organized and about as well maintained as a dozen people can possibly do. They keep all their development stuff out on the pages so you can get involved with what's what as they do it.
I think a Peppermint question will get answered.
I think Peppermint got started up about the same time Lubuntu got cast out of the Ubuntu family tree as they were all getting pretty far from the Ubuntu tree at that time. Peppermint will run on your low hardware level, supposedly, and it HAS the documentation level you will need. Peppermint is noted for being quick and easy enough to learn, but learn you shall as it is a different approach to the web and computing.
Note: some folks will say that Chrome OS was a reconsideration of some of the ideas behind Peppermint and some folks will say that Peppermint was a reconsideration of some of the ideas behind Chrome OS -- both use the web (and all those super strong server farms) to energize their speediness. I think Chrome OS does a more seamless job of it since Google actually owns the server farms they use to superpower Chrome OS.============
So, here are two Ubuntu based distros you can try that seem to have the internal organization level that the whole litter of Puppies seem to lack.
Beyond this, I can't say -- I intend to support folks on Linux Mint Mate 64 bit
as after all my looking it is the best XP replacement out there that looks and works most nearly like XP (least surprises, least learning).
But you need 512k of systems memory and a 600 mhz to 1 ghz Athlon processor to run it well enough.
It will run with less, but not well.
Folks tend to forget that XP started out as a 32 bit only Pentium class operating system and the early early machines sometimes only had 256k of systems memory.