Increasing Battery Life with a RAM Disk
I decided to try something different - something that I've done in the past, but have never really thought about using on something as old as my PowerBook 170 - using a RAM disk.
In an effort to increase my battery life, I slowed down the processor, opened ClarisWorks, turned off the backlight on the screen, and turned off the hard drive (see 30 Days of Old School Computing: Computing at Work with a PowerBook 170).
Everything was going just fine until I decided to save the article.
I managed to run the spell checker (which needs the hard drive running) and save the document. It wasn't a moment too soon, because as soon as the article was saved, the battery died and the computer shut off.
I decided that it would be a good idea to make a short list of programs and utilities I need to do simple work and load it into a 4.5 MB RAM disk.
I chose the following items:
- Minimal install of System 7.1, including AppleTalk, SuperClock!, and the PowerBook Control Panel.
- ClarisWorks, for all of my Word Processing needs.
- TeachText (because it's smaller than SimpleText).
- A few Web pages converted into TeachText documents.
- A few simple games like Brickles and Cannon Play.
After loading all of these files, I still have close to a megabyte available for storing files.
The beauty of having 8 MB RAM in this PowerBook is that not only can I install a small application or two on the RAM disk - I can install the operating system and shut off the hard drive for good.
Booting from a RAM disk can be a really handy feature (Unfortunately, you can't boot G3 and newer machines using a RAM disk). Using the RAM disk instead of the hard drive should also make the battery in this 'Book last a lot longer.
Putting It to the Test
When I wrote my last article, the battery held it's charge for about 30 minutes. I'm hoping that it will last a little bit longer today.
It takes a lot of power to spin up the hard drive, and by the time I was finished writing my last article, two of the three low charge warning dialogs had already come up. I'm really glad that I didn't loose the entire article, because I spent my entire break writing it.
So far it has been 20 minutes since I started writing this article, and the battery is still has about 50% of it's charge left. That may not sound like a lot, but I bought this battery back in 1998 when I still had my old PowerBook 140, which makes it a little over eight years old.
That's pretty good for a battery this old, especially considering the fact that the battery in my Lombard doesn't even hold a good enough charge to keep the machine asleep.
At 30 minutes, it's still reading 50% charge. I wonder how much longer this battery will hold out.
Something that I forgot to point out in my last article was how much I love the PowerBook 170 screen. Yes, it may be 1-bit black & white, but it's tack sharp - even sharper than the screens on my compact Macs. Talk about a high quality screen, you can see this thing at all angles, and I mean all angles.
I know that is what you would expect from an active matrix screen, but I've noticed that even on newer TFT screens the image will invert if you look at it from the wrong angle.
And because the display is 640 x 400, you can see more on the PowerBook than you can on any compact Mac, which is great when you're looking at multiple instant message windows or need to see an entire picture at once.
Sure, you can see a lot more on a 2560 x 1600 display, but when you've been working on compact Macs as much as I have over the last few weeks, 640 x 400 is extremely roomy!
If anyone has their own "old school computing" story or wants to join me, please feel free to email me.
Until next time, keep it real, keep it simple, and keep it old school.
- Mac of the Day: PowerBook 145, (1992.08.03. About 70% faster than the 140, the 25 MHz 145 was quite a value.)
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