Should I leave my computer on?

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By Catherine Holland By Catherine Holland

Q. I’ve heard conflicting opinions about this, so I hope you can help me: Should I leave my computer on all the time or turn it off when I’m not using it?

A. Ultimately, you have to do what you are most comfortable doing, but I leave my computers on all the time for a number of reasons: First, most catastrophic failures occur during power up when that surge of electricity hits the cold computer components. Leaving a computer on maintains a more stable operating temperature.

Hard drives are rated by hours between failures and a typical hard drive today is rated at 100,000 or even 200,000 hours. Even at 100,000 hours, that’s a little over 11 years of 24/7 operation, so wearing out a drive is not a concern.

For power conservation, I have my monitor set to go dark after two hours of non-use. Depending on your version of Windows, you can review your Power Management settings by going to the Control Panel > Display > Screen Saver > Monitor Power, Power Management, or words to that effect. You’ll see settings for your monitor, hard drive and standby. I have my desktop computers set to “Two hours, Never and Never.”

If you’re going to be away for a few days, it makes sense to shut everything down, but there is no hard and fast rule for that. If you do decide to leave your computer on, be sure to restart it once a week to clear out memory and refresh system resources.

Q. Is it true that I can get a virus by viewing email in the preview pane of Outlook Express?

A. There are a few rarely seen viruses that can launch from the preview pane. It's unlikely, but it can happen. If you want to play it super-duper safe, you can disable the preview pane by clicking View > Layout and removing the check mark that appears next to Show Preview Pane.

Q. Is there a way to compute how long it's going to take to download a file?

A. There sure is. In fact, there are two methods. Let's say you created a photo album of last summer's kayak trip through the Everglades. Your “Mosquito Swarm at Sunset” photo is so good, you're itching to share it with others. Collectively, your photos are 3.2MB in size, so for recipients with high-speed Internet access, it will take scant seconds to download. But what about poor Uncle Rudy who is using an ancient 28.8bps modem with his dial-up connection?

To manually do the math, you have to convert the 3.2MB to kilobytes, bytes, then bits, and divide by 28,800 to yield the number of seconds. Then divide by 60 to determine the number of minutes. That’s a lot of work, particularly if you’re not too crazy about Uncle Rudy in the first place.

A much easier method is to use the Martindale Download Calculator. Enter the size of the file, the type of Internet connection and presto! A 3.2MB file will require 16 seconds to download using cable, but almost 17 minutes for Uncle Rudy.

Mr. Modem's Sites of the Week:

Ghost Photographs
Do you believe in ghosts? Whether you do or not, take a look at some of the mysterious pictures. The site also includes images that are known fakes or have a natural explanation -- or do they?

Historic Tale Construction Kit
Whether you are a history buff or just trying to look busy at work, this site lets you create your own story from the Middle Ages, complete with warriors, beasts, and shamans. When you complete your story, you can submit it to the site so others can view it, save it, or send it to your friends and waste their time, too.

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