Terry's Computer Tips - Newsletter
October 31, 2005

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Volume 1, Number 20 -- Monday, October 31, 2005
Part 1 | Part 2 | Part 3

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4.  Distributed Computing -- Putting PCs Spare Time to Work

My friend Larry Braud, who is a Terry's Computer Tips reader and a fellow volunteer instructor at the Cajun Clickers Computer Club, wrote me to suggest an article on one of the many distributed computing projects.

I have been participating in SETI@home, the earliest of the distributed PC computing projects, for over six years. This is the project that validated the usefulness of using hundreds of thousands of personal computers (or millions of them!) to run analyses of small chunks of data.

Almost all distributed PC computing projects are designed to run their analyses when the computer is otherwise idle, although some projects can be run all the time if the computer's owner wants it that way. In effect, this widespread network on individual personal computers becomes a massively-powerful supercomputer.

The advantage of distributed PC computing is that the scientific project can (1) use the computers of volunteers without having to purchase or rent computer resources, and (2) with huge numbers of personal computers, they can actually have "systems" that are much more powerful than today's fastest supercomputers.

I started several of my computers running the SETI@home project's analysis package during April, 1999. Since then, I have had as many as four computers crunching data, and as few as one. SETI is the Search for ExtraTerrestrial Intelligence.

The SETI@home project analyses recordings of radio telescope data, looking for spikes and signal transitions that might indicate extraterrestrial life. When analysis of a data packet looks interesting, the scientists' first step is to send the same data packet to someone else to make sure that the results are the same (yes, some people have attempted to fool the system). The Seti@home project is run from the University of California at Berkeley.

The original Seti@home project was run on custom-written software. After the resounding success of the project -- in getting volunteers' computers to run the project, not in finding ET -- a more general distributed-computing software package was created called BOINC.

There are some major advantages to BOINC for distributed processing. First, in addition to the automatic submission of results and acquisition of new data to process (both of which were part of the original SETI@home software), BOINC allows the project to send automatic updates of both the BOINC software and any project-specific analysis procedures.

Did you notice that I'm referring to "the project" now and not SETI@home? That is because BOINC allows you, the individual computer owner, to decide which project you want to join, out of the many distributed computing projects being run.

The field of medicine is one of the major fields that is benefiting from distributed PC computing. Current BOINC-powered projects include Predictor@Home (biology), Rosetta@Home (biology), PrimeGrid (mathematics), SZTAKI Desktop Grid (mathematics), Einstein@Home (physics), LHC@Home (particle physics), SETI@Home (SETI), and Climateprediction.net (weather). BOINC is not the only game in town, either.

Another major medical project, Folding@home, is based out of Stanford University. This project is analyzing the process of protein folding, which is a critical and fundameental part of biology that is not yet understood. When proteins do not fold correctly (i.e. "misfold"), there can be serious effects, including many well known diseases, such as Alzheimer's, Mad Cow (BSE), CJD, ALS, Huntington's, Parkinson's disease, and many cancers and cancer-related syndromes.

If you would like to help in any of these distributed computing projects, or just to read more about them, visit Folding@home or Seti@home. Both of these have good explanations of their processes, which are designed to be easily understood. Of course, either would be happy to let you download their free project software and start helping.

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5.  External Hard Drive Enclosures

External hard drives are great for backing up your computer. They enable you to accomplish some of the important facets of backing up:

• you can back up your entire hard drive or your your boot partition (usually these are the same thing as most Windows XP computers come with one big C: drive) (see my June 20th issue)
• you can back up your individual files (except those that are locked by Windows)
• you can easily back up individual files that have changed -- either from the whole drive or just from the directories you specify (see my June 20th issue),
• and they enable you to disconnect the drive so that it can not be affected by a trojan, virus, worm, lightning storm or user brain freeze -- so you have a real, useful backup sitting on the shelf.

You can also build your own external hard drive. It is not difficult and it can be a much cheaper alternative to buying an external drive, especially if you have an old hard drive sitting on the shelf.

If you plan to put a BIG drive in an external drive enclosure, check test it promptly in case you have to return it. I have an external enclosure that's about 2 or 3 years old, which was before hard drives had broken the 132 GB barrier. WinXP Pro SP2 will only use a maximum of 132 GB on the drive, even if the drive is larger, despite the manufacturer's web site that says the case will handle drives over 250 GB.

While WinXPSP2 removed the 132GB limitation from IDE drives, but this problem was apparently in the enclosure's interface hardware, as other people have reported successfully building external hard drives with large drives and without having to install special drivers Of course, huge external drives are available in retail packaging. Most of them come with special software to easily back up your system.

Don't forget the other end of the external hard drive spectrum - you can build or purchase your own small 2.5-inch hard drive enclosures, too.

Read more in my External Hard Drives article.

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6.  Running Your Computer 24/7

I am occasionally asked "is it ok to leave my computer on overnight?" or "can I leave my computer on all the time?"

My answer is a resounding "yes, I do." My desktop, my wife's desktop, my Linux box and my Home Theater PC (www.terryshometheater.com/htpc) all run 24/7.

My notebook does not and should not -- the issue with a notebook is that the LCD screen's light sources will dim and wear out. If you have an LCD screen for your desktop, be sure to use a screensaver and the power-saving option to "turn off monitor after ___ minutes of non-use."

If you choose to let your desktop computer run 24/7, be sure to have it on an uninterruptable power supply (UPS), preferably one that is 600 to 1000 VA. Most come with a USB cable and software to run on the PC to monitor the status of the UPS and the power _to_ the UPS.

If your power goes out, the software detects that change (via the USB cable from the UPS to the computer) and triggers a safe shutdown of your computer.

If you have an LCD monitor, be sure to use a screen saver and the Windows power-saving functions to turn off the monitor when it is not in use. The light sources for an LCD monitor is are several fluorescing tubes -- they will dim and eventually burn out. Even if you use a screen saver, you should have the screen power-off after not more than an hour of non-use. This will protect the monitor's life.

I do not believe that LCD monitors suffer that fate that CRT monitors do. CRT's have been known to burn an unmoving display into the phosphor of the tube. That problem was more common in the old monochrome monitor (green/black) days. But, I wouldn't want to try to burn a 19" monitor to see if I could do it.

Similarly, my 52" rear-projection television's instructions said not to leave static images on the screen (from game consoles or unchanging displays from my Windows-based home theater pc) to prevent burn-in of the screen.

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Continued in Part 3

Volume 1, Number 20 -- Monday, October 31, 2005
Part 1 | Part 2 | Part 3

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Copyright © 2005 Terry A. Stockdale.  All rights reserved.