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issue87:labo_linux

One of the ways Linux has been promoted in the past was as a replacement operating system for older computers. As Linux distributions evolve and change, they often demand more resources. Last month Les, Olly and Tony of the Full Circle Podcast banded together to install Ubuntu on 3 systems: one which barely met the 700MHz, 768MB RAM minimum requirements, a Pentium 4 1.6GHz-based system, and a Core 2 Duo-based system – with poor results for the first two installs. Check out their experience by downloading Full Circle Podcast #41: http://fullcirclemagazine.org/2014/06/08/full-circle-podcast-episode-41-trusted-to-fail/

At our computer reuse project, our minimum build is a Pentium 4 class computer running at 2.4GHz or better with at least 1GB of RAM and an 80GB hard drive. We set this minimum rather arbitrarily, a 2GHz computer would work just as well, especially if you increased the RAM to 2GB. For this article, I randomly picked a Pentium 4 class machine from our back shelf. The machine I picked was a Dell Dimension 3100 with the following specifications: Pentium 4HT 2.8GHz, 2 x 256MB DDR2 533MHz (512MB total), Samsung HD080 HJ/P 80GB Hard Drive, Sony CD-RW CRx217E, 8MB onboard video RAM.

When Les, Olly and Tony approached their build, it was to test full-blown Ubuntu with Unity on all 3 platforms. This is a great method for modern hardware, but it’s a bit like trying to put a 1.6L engine in a 2-tonne truck - you just don’t have enough power to drive the interface. On “other” platforms, we all know the gulf between the minimum requirements and recommended requirements for a program can be enormous.

The solution is a two-pronged approach - upgrade what hardware you can and use software/an interface that works with your hardware. Of course you have to keep the end user in mind when changing the interface, but the great thing about Linux is that it’s so customizable. With a bit of customization you can ease someone’s transition to Linux. Take the screenshot of Xubuntu 14.04, shown left, for example.

Normally when we build a refurbished computer, the first step is evaluating the computer. Our Dell Dimension 3100 has several shortcomings:

First there is no PCIe 16x or AGP expansion slot in this particular model of computer. PCIe 16x video cards are the current common standard. AGP, while old, is relatively easy to find on Kijiji, eBay or from most places that sell used computer parts. The Dimension 3100 actually has a PCIe 1x slot, so it’s possible a better video card could be found, but in our computer refurbishing project we’ve seen exactly one PCIe 1x video card over the past year.

Our Dimension 3100 also had only two memory slots, thereby limiting RAM options. On the positive side of things, the RAM type was DDR2. While DDR2 isn’t as readily available as DDR3, it’s a lot easier to get than older DDR.

Our machine also had a CD-RW drive. As a standard practice at our computer recycling project, we always replace CD-R or CD-RW drives with at least a DVD-R or DVD-RW drive. One of the problems the Full Circle Podcast crew mentioned was the limiting size of the CD drive in one of their machines; this won’t actually be a problem for our install since we won’t be installing using the same ISO image.

Back in the “old days” of Ubuntu 4.10, the installer was text based. Graphical installers are all the rage these days because they’re usually part of a live DVD so you can try the environment before installing. Graphical installers are nice, but text-menu-based installers are often faster and give you more control over your install. Instead of grabbing the main 32-bit or 64-bit installer from http://www.ubuntu.com/ I grabbed the network installer (a mini.iso) from the alternative downloads link: http://www.ubuntu.com/download/alternative-downloads

Depending on the machine, and the person who wants the machine, I’ll often dig a little deeper into the machine specifications. Our Dimension 3100, while containing only a single 2.8GHz Hyper Threaded core CPU, actually supports 64bit instructions. However, since we have only 2GB of RAM available, we went with a 32-bit version of the network installer.

The fastest method for installing the mini network ISO would be to use Unetbootin to create a bootable network install USB key: http://unetbootin.sourceforge.net.Our Dimension 3100 supported booting from USB key and we set it to boot from our key, but it didn’t work. We double checked the BIOS settings to make sure the ‘USB no boot’ option wasn’t set (it wasn’t). USB was enabled in the BIOS. Our USB keyboard and mouse worked fine in all ports.

The culprit could have been our USB key. If a key isn’t unmounted correctly then data corruption can occur. But in this case the culprit was the USB KVM (Keyboard Video Mouse) switch we were using to switch between 2 computers. Our experience has been that USB-based KVM switches tend to draw off enough power to cause problems with USB keys. The switches appear to work fine because USB Keyboards and Mice work when plugged in. But anything that needs a bit more power doesn’t work with the USB KVM switch (which is the reason some USB KVM switches have a power connector for external power from the wall, of course they almost never come with an external power adapter). Once we set up the computer independent of the KVM switch, it booted to the USB key and we were able to start the network installer.

Earlier I mentioned that the network installer is pretty fast, but, if you have a slow connection, your install may be quite slow. To install the base system (command prompt) it took around 25 minutes on our single core Pentium 4 (start to finish). This time includes the time it took to respond to several questions the text installer asks. While fast, the text installer also asks more questions than the graphical installer (questions like which proxy to use).

Once the install was finished we were left with a console login. To make the computer more useful to general computer users, we needed to install a desktop environment. Unity is a great desktop environment – the more I use it, the more I like it, but it doesn’t work well with all video cards, and is a bit of a resource hog compared to XFCE, LXDE and Enlightenment.

Normally we install the Xubuntu desktop environment for all the Linux computers we build. Standardizing on one desktop environment makes it easy to support someone when they’re having problems. To install XFCE plus most of the packages found in the Xubuntu desktop it takes only one command:

sudo apt-get install xubuntu-desktop

Enlightenment is a wicked fast desktop that works well on just about any video card. Initially we installed this because it installs almost 1,000 packages fewer than xubuntu-desktop. The problem we ran into was that we also needed to install the xserver (xserver-org) and a login manager (lightdm). Installing these packages took only another 10 minutes, but we really didn’t have a good selection of software afterwards, so we just ended up installing xubuntu-desktop.

Xubuntu worked surprisingly well considering the 8MB of video RAM. We’ve worked with 1MB and 8MB video on older Small Form Factor Compaq EVOs (D51) and found all kinds of problems: screen tearing, choppy video, stuttering. Even with a 32MB video card the Compaq EVO never worked very well for us. And on other generic systems which had only 1MB-8MB of video, an instance where the location bar of Firefox would sometimes blacken so you couldn’t see the text until you clicked back in the location bar.

We watched a youtube video on our Dimension 3100. The video displayed with slight pauses but it wasn’t stuttering enough to make it unwatchable. Firefox felt a bit sluggish, but there were no display problems and no screen tearing. Programs generally loaded fast (of course nothing like a high-end quad core, but with enough speed to get work done).

The takeaway from all this is that it’s possible to install a working Linux-based desktop environment on low-end hardware that would suit the “average computer user.” Video card upgrades (if possible) and some extra RAM go a long way.

The AGP video architecture might be old by today’s standards but a 256MB or 512MB AGP can still give your system a big boost. If you are looking for video cards of this vintage, we found it best to go with NVidia-based cards since you can normally find proprietary drivers in the “Additional Drivers” program (in Xubuntu 14.04 you can find it bundled in Settings Manager). We recently put a 512MB AMD Radeon HD 2600 AGP in a system and it performed worse than a 128MB NVidia card simply because of the drivers available.

For extra parts, check to see if there’s a local computer refurbishing or recycling project in your area; parts can be a lot less than you’ll find on eBay, you save yourself shipping, and you have somewhere you can go back to if a part doesn’t work. Sites like kijiji are awash with computers and parts. If you buy a second-hand computer from Kijiji there are a few things to look for (if you can, not all sellers will allow you to fully examine equipment):

Check the USB ports, are some damaged, are they filled with dust, or tar from cigarettes? Don’t buy anything you don’t feel is well maintained.

If you can examine the inside of the computer. Look for bulging or blown capacitors on the motherboard. Check there are no obviously missing parts (battery, heat sinks, hard drive, RAM, etc) and that things look in good order. A look inside will also tell you if the computer has been well maintained (dust, tar or worse). Systems often can turn on with blown capacitors, but might behave erratically, it’s best to stay away from these systems, even if you intend to replace the capacitors. If capacitors are blown, there might be something else that has electrical damage that’s less visible.

Again if the seller is willing, watch the system boot, even if it’s just to the BIOS. As a computer refurbisher, we used to recommend that people who buy on Kijiji also ensure they have a Windows COA.

Check the drives. Does the CD/DVD drive even open? We see lots of computers come into our project that have nice DVD writers that have been jammed with broken CDs, pencils, money, and other things that should never go in a DVD drive. If you’re buying an older Dell computer, many Dell systems have 4 small lights on the back. Check to see that all the lights are green, if a couple are orange there is a problem with the computer. Dell provides documentation on their website on the diagnostic lights for each model of computer they sell. I’m not endorsing them here, just mentioning a useful tip that leads to my next point.

When you can, get as much documentation about the model of system (or motherboard if it’s a generic aka “whitebox” system). Good documentation will tell you about expansion options (how much RAM a system will take, which version of PCIe the system supports (2.0, 3.0, etc.) and can help when troubleshooting problems.

And if all else fails, try a different distribution. The great thing about Linux is there’s always choice. Choice gives us a wonderful array of desktop managers: KDE, Gnome, Unity, WindowMaker, Enlightenment, LXDE, BlackBox, etc. Choice gives us a wonderful array of software too, so if something’s just too heavy for your hardware try a lighter option: use Abiword instead of LibreOffice Writer (or even something web based like Google Docs). Choice is the reason why Linux is still great on older hardware.

issue87/labo_linux.txt · Dernière modification : 2014/10/30 16:11 de andre_domenech