Second-hand computers

There are a number of organizations who work in this field, taking old computers and setting them up for use by disadvantaged people. E.g.:

• Computerbank, Australia
• Computer Component wiki: "Used Computer" has a list of organizations accepting donations of old computers
• a list of nonprofit organizations accepting donations of old computers

Multi User computing

Since some years computers have enough resources to be used by more than one user ( even using a graphical interface ). What is needed is one or more graphic cards supporting more than one monitor and some USB keyboards and mice.

• Build a Six-headed, Six-user Linux System, (Linux Gazette Article)

Resistance to sand and dust

Any moving parts will be particularly vulnerable.

If a conventional computer system is used, damage can be reduced by:

• Keeping the computer unit on a desk, not on the floor. Even with a mesh over the fan inlet, dusty air near the floor will harm the computer over time.

Power issues

For computers using mains power, low power consumption is still best:

• It causes less heat, and makes cooling easier.
• Less heat means less ventilation needed, which means dust entering the casing and thus greater reliability.
• Also consider the embodied-energy of the product; the energy used in the production phase of the computer.

Low usage options

The XO-1 (laptop)^W is planned to use 1 W of power or less. This is a great boon where power is limited or expensive.

However, in many contexts, where mains power is available, moderate power consumption is not a big problem, and it may not be worth the hardware cost to use ultra-low power consumption items.

Battery

While less than ideal from an environmental point of view (particularly where recycling options are not available), battery storage adds considerably to a computer's utility when used outdoors or with intermittent sources of power. Since batteries are also expensive, a computer with low power consumption is probably preferable to having more battery capacity. Many battery types also lose capacity over time, a process that can be accelerated by certain patterns of charging and discharging depending on the battery type.

One problem in locating new or used replacement batteries for laptops and similar devices is that most manufacturers will use a custom/proprietary form factor that prevents cross-compatibility with other brands and model lines. Norhtec's low-cost Gecko laptop uses eight standard AA sized rechargeable cells instead, eliminating the need to find a battery specifically designed for the device. Because of the broader market for standard battery types, prices can likely be more competitive.

To restore battery functionality to a laptop with a dead battery that has a non-standard form factor, it's possible to construct an external battery by wiring enough individual cells in series to create the voltage needed, and connecting that to the computer's DC input. With AA batteries this can be done with very inexpensive parts, but charging the cells in place would require additional circuitry. Power input jacks are much more likely to be of a standard type than the battery of the laptop, increasing the odds they will be available locally and inexpensively. Another method of restoring function would be to disassemble the original battery and replace the dead internal cells with functioning ones of the same number and type. This may be preferable if charging during operation is required.

Local energy production methods can be intermittent, which presents restrictions on usability if no power storage at all is in place. (#Crank power) is not unpredictable in the same way that {[solar power|solar]] or wind) power can be, but without any form of power storage the computer would turn off the instant you stopped cranking. Needing to generate power constantly to prevent immediate shutdown would make it considerably more difficult to use a hand-cranked computer since the hands are also needed for other tasks, but with foot/pedal power this would not be as much of an issue.

• - However, having the use of a computer only "sometimes" may still be an improvement over the having the use of a computer "never". -- In many places even mains power is not available 24/7, and people still prefer that over no mains power.
  Additionally, in some applications battery back-up can be made to palliate the inconvenience of intermittent power. (A pretty standard solar- or wind-recharged system, which have been made with technologies as primitive as recycled car batteries for decades now.)

Crank power

The XO-1 (laptop)^W is likely to have an optional hand-crank or foot-pedal, which will be a separate unit (to avoid damage to the computer by the physical stresses of cranking).

CPU (chip)

(Make Table - cost, speed, suitable o/s)

The CPU is a major factor in a computer's speed, power consumption and software compatibility. The clock rate ^W of a processor in MHz or GHz gives only a very rough idea of its capabilities unless comparing similar models, so it may be better to rely on real world tests to determine whether the system can perform a given task adequately. In some cases, processor intensive tasks (e.g. video decoding) can be offloaded to other components of the computer, allowing unbroken playback when otherwise the CPU alone might be unable to keep up.

Generally, recently made processors often have better power efficiency than older models, due both to miniaturization of components and active power saving measures not present in earlier chips. Used systems can have a low initial cost, but a power-hungry used model may present a false economy, depending on the cost of electricity and the amount of time it will be in use. Over time this will be less of a problem as inexpensive power-efficient models reach the used market at progressively lower prices.

Processors based on the X86 ^W architecture are found in most personal computers that exist now, which generally means broad compatibility with available operating systems and other software. Current X86 processor model lines with low power consumption include AMD's Geode^W and VIA's C7^W, both seen in different revisions of the OLPC-XO, and Intel's Atom ^W line which is found in many consumer netbooks.

ARM ^W based processors are another low-powered option if X86 compatibility is not considered essential. Processors of this family are frequently seen in phones and other handheld devices, but inexpensive laptops with processors and tablet computers with ARM processors also exist. Power consumption can be significantly lower than comparable X86 chips, but running most commercial software designed for X86 systems (e.g. a full Windows OS) is not ordinarily possible. This is less of an issue with open source software and operating systems, because an ARM version can be compiled by someone from the source code and redistributed.

Is a Geode (processor)^W suitable? Low power, used in Embedded system^W.

Media drives

Unless otherwise stated, the drives shown are for desktop systems.

Prices of CD and DVD drives and recordable media have declined to the point where there is no longer much of a price advantage to the older CD format either per disc or per drive. DVD drives are backwards compatible with the CD format, and DVD-RW drives also retain CD-RW write capabilities. In both cases, rewritable discs are more expensive than ordinary recordable discs that can only be written once, making them best suited to applications where the contents are only needed temporarily (e.g. testing). Since DVD discs hold many times more data than CDs but don't cost significantly more, the primary advantage of CD-R media today is playback on devices like audio CD players. Some audio CD players, particularly older models, are not able to play CD-R media though.

DVD drives and media come in a confusing array of varieties. Most notably, some drives will record to DVD-R but not DVD+R discs or vice versa, and some are unable to write to higher capacity dual layer media. Conversion of other video file formats to DVD can require a lot of time on a computer that's not moderately recent, and importing video from a source like VHS requires special hardware. DVD-RAM is a specialized disc format not compatible with stand alone DVD players.

Blu-ray has emerged as a successor to the DVD format, except in China where a variant of the competing HD-DVD disc format is still in use. Disc capacities are many times those of DVD media. As of 2011 there are significant premiums on Blu-ray drives and recordable media compared to DVD, but these have gradually diminished over time.

Monitors

The cheapest option will often be second-hand monitors.

Cathode Ray Tube^W monitors will most often be cheaper and more accesible than LCD^W monitors. Be warned, however, of the risks in accepting free CRTs. You may end up with a dead monitor and a recycling fee.

Some brands to look for:

• Panasonic
• Dell
• Packard Bell (suprisingly long lasting)
• ViewSonic

New monitor options for desktops

Low-cost; low power consumption is better if possible. What are the options?

Data storage

The main options for storage are:

• hard disk (better value; computer must be protected from physical shocks and bumps.)
• flash (more expensive; no moving parts, so more tolerant of bumps (which is why it is used in the XO-1.)

The XO-1 (laptop)^W has no hard disk, using a (flash drive instead? how is data stored between sessions?)

Flash does not equal volatile. Flash memory^W is non-volatile (i.e., data is retained between power-offs). In particular, most PDAs use non-volatile flash memory.

RAM

Some Linux systems (see below) require as little as 4 MB of RAM - though more obviously gives more options and better function.

(Note - this table is based on my limited knowledge, and may not be correct - please help improve it.)

Operating system

The requirements for an operating system are:

• Free
• Easy to setup
• Easy to use
• Excellent documentation is critical.
• Low resource use

Windows

Windows is the best known system; however, we don't want to spend this much money, even if we have a computer which can run Windows.

Pirate versions are common in some developing countries, but:

• Obviously Appropedia can't endorse pirate software, and
• By using Linux, we encourage and tap into a community of users and open-source programmers who are likely to support our efforts.

Windows also is more resource-hungry, less reliable and stable than Linux.

Windows XP is not supported by Microsoft any more (as of April 2014).

Windows 7 and 8 require 2 GB (= 2000 MB) of RAM and modern processors for useful operation. Therefore, these Windows versions are no alternative for older computers with 256 MB of RAM to 2 GB of RAM. To continue using those computers instead of having them become electronic waste, an efficient Linux distribution like Lubuntu Linux (from 256 MB of RAM) is a good replacement for Windows XP.

See How-tos: "Installation Tips: How to replace Windows XP with Lubuntu Linux" (PDF)

Windows 98/ME (not supported by Microsoft any more) seems to be able to run Open Source applications faster than Linux on old hardware. Was also able to get more large Open Source applications to run on a Windows ME machine than on a Linux machine with a distribution geared to older systems (on the same computer).^{[expansion needed]} My source for this was my own experience. I used a laptop running Windows ME and later on the same one running Linux, ran the same Open Source applications and saw a speed difference. I've also seen this mentioned on a few Linux blogs by users who run both operating systems. -- comment by anonymous contributor. With that in mind, ReactOS might be a good future solution (but is currently alpha, not suitable for everyday use . ReactOS is an Open Source operating system attempting to be compatible with Windows NT (and future versions) and to give compatibility with Windows native drivers, while using much less system resources.

Linux

Using a lightweight version of Linux specially designed for older computers may be the best option. Even 486 machines can run with some of these, although without a modern browser with flash etc. There is a wide choice of Linux flavors, called "distributions", which can be confusing to the newbie.

Linux is also Free Software Free software^W (also known as FLOSS FOSS (see: Libre^W).

As of March, 2014, Lubuntu Linux (from 256 MB of RAM) is one of the best lightweight Linux versions available and a very easy to install replacement for Windows XP.

See How-tos: "Installation Tips: How to replace Windows XP with Lubuntu Linux" (PDF)

How to choose a Linux distro

• Use a tool to help you choose - or take all of these tests, as they all give a different perspective: zegenie Studios Linux Distribution Chooser (most thorough, and multi-lingual), (:^tuxs.org) Linux Distribution Chooser (simple), or polishlinux.org's Distro chooser (moderate).
• Assume that you'll have to try more than one distro before you find one that works and works the way you want.
• Make a LiveCD^W and try it out. In the end, you'll pick your distros based largely on compatibility with your system, including hardware detection.
• Install the operating system to a separate partition - this makes it easier to try new distros, and to upgrade.

MorphOS

Strengths:

• MorphOS^W has a very "small footprint" and installs in less than 15 MB.

Weaknesses:

• Lack of good, usable programs. Even the web browser is apparently not complete.
• Mix of proprietry and open-source. Not as open as Linux - meaning users are dependent on the owners and how good a service they provide.
• Community of users and developers is not as large and active as Linux; Users are far more rare than Windows users, as well. As a result, getting support will be far more difficult.

Essential software

• Web browser^W
  • Mozilla Firefox^W, Konquerer^W, Epiphany (web browser)^W, Galeon^W
  • Links, Dillo work on low resource systems
• Word processor^W
  • Abiword^W is very popular and has low hardware requirements
  • If plain text editing^W is the only requirement, Vim (text editor)^W, Mg (text editor)^W, Nano (text editor)^W, and Pico (text editor)^W work well.
  • For a programming editor, SciTE is excellent. It can do many of the things a word processor can do plus anything a text editor can do.
• Adobe Acrobat^W, Foxit^W, or other program to read (and perhaps write) PDF files.
  • There are several open source Linux pdf readers. Evince is quite a good one.
  • Writing PDF files can be achieved with OpenOffice, LibreOffice, and other word processors.
  • XPDF is available on some Linux distributions and I've read Sumatra (also available at Portableapps.com) for Windows users is based on it. There's also a Windows version of XPDF available at the GnuWin32 project at Sourceforge.
  • Ghostscript can also create PDF files with a command line program.

Desirable software

These are not essential, but would be a plus:

• Windows application layer
  • Wine (software)^W
  • Cedega^W (formerly Transgaming WineX, based on Wine)
• Chat program
  • Instant Messaging: Pidgin (software)^W, Trillian^W, ayttm^W
  • IRC: X-Chat^W, BitchX^W, irc it
• Office software (word processing, spreadsheets).
  • It is desirable that the user can open and save to standard (i.e. Microsoft) format files, such as Word and Excel files. This can be achieved, usually, by using OpenOffice.org^W.
  • "Lighter" programs such as Abiword^W are often used in light versions of Linux for older machines. However, they have more problems opening some Microsoft files properly, compared to OpenOffice.

Low resource software

Software that works on older computers: (These work on Linux and Windows unless noted.)

• Graphics
  • mtpaint,figurine (Winfig on Windows but takes more resources), flphoto
• Video
  • flxine with libxine (There is a Windows port of xine.)
• Audio
  • Timidity++, sox, gramofile, abc2midi, abcm2ps, mhwaveedit (Linux only)
• PIM
  • fltdj, tux_todo, hypertree, lcal

Security

An important part of minimizing maintenance problems and ensuring reliable operation is keeping the computer safe from viruses^W and other security risks.

If you are using Linux or Apple, your system is relatively secure to start with. However, basic security measures should still be followed.

Windows machines are prone to security problems, and this must be taken very seriously. It is very strongly recommended that the system be hardened, i.e. made more secure.

The most essential steps include:

• Using an up-to-date firewall^W when connected to the internet.
• Using an up-to-date anti-virus program when connected to the internet.
• Never operating an account without a password. This default setting of no password is one of the things that makes Windows computers very vulnerable to attacks and consequent problems.

All these things can be done at zero cost by choosing free software and using free guides where needed.

This is just a start - see the links below for more info.

More information:

• Hardening^W in Wikipedia.
• Do a google search for hardening Windows XP

Maximizing performance

In order to make the most of older equipment, it is valuable to tweak the system, using certain low-risk methods.

One simple method in Windows XP^W is to change the setting

More information:

• tweaking^W in Wikipedia
• TweakHound's Super XP Tweaking Guide - SP2 version 2.0 Final Follow the "All Levels" suggestions for the safest tweaks. This needs to be checked to make sure it's a suitable guide to be linked from here.
• Do a google search for supertweaks

Further reading

• Search for more information, e.g. google:appropriate-information-technology, google:ICT4D or google:ICT4D-portal.

Organizations

• http://www.inveneo.org/, a non-profit working to distribute ICT internationally
• http://wiki.laptop.org/go/Home, One Laptop Per Child wiki at MIT
• Wireless Networking for Developing World has a downloadable book (CCDN license) and a wiki on related projects, etc
• Geekcorps Desert PC effort, and here is a link to the Desert PC Spec Sheet (pdf)

Articles & discussions

• Forum discussion of "thin PC" running Puppy Linux - no hard drive, just 128 MB flash drive and 256 MB RAM. Sold in US for $189 (in July 2005).
• Which Linux suits the third world? - discussion at linuxquestions.org.
• GNU/Linux on old hardware - polishlinux.org
• Linux and Bridging the Digital Divide - appears to be a page by an EWB-ISN (Australia) member.
• Information and Communication Technology - National Policies & Case Studies. The Communication Initiative" (summarized in The Drum Beat - Issue #370, "ICT National Policies & Case Studies").
• Guide to Low-Cost / No-Cost Online Tools for People with Disabilities
• Quick guide to low-cost computing devices and initiatives for the developing world infoDev.org (a World Bank site) - many projects and devices are mentioned.
• Low-cost computing - Network Magazine India - gives a few applied examples.

Other pages with a similar focus to this one

To help keep in touch with similar projects.

• Links on the Social Software site - older page, some links out of date. (Link does not seem to be working any more. Any other links on this topic?)

How-tos

• How To Assemble A Desktop PC at Wikibooks.
• Some windows tweaks
• Installation Tips: How to replace Windows XP with Lubuntu Linux, for Computers from 256 MB of memory (RAM),
  PDF, March 2, 2014