Reader Feedback: Battery Conservation Tips

Most of the reader feedback to our editorial on battery conservation techniques revolved around the use of RAM disks. Here are a few examples:

From Ray Bonoan:
"If you've got enough RAM, run the computer using a RAM disk as your startup volume. A stripped down OS 8.5 System Folder and a word processor, such as Nisus Compact, requires of RAM disk of about 27 MB. You can save the the System Folder & any applications as a disk image using Disk Copy (thereby avoiding the danger of having 2 system folders on your hard drive at once) and then mount the image & copy the files to a RAM disk whenever you want to run the computer off battery power."

From Larry Becker:
"Back in December (Jan issue) Macworld ran a detailed sidebar about setting up a ram disk. I have a G3 PB w/192mb RAM so I thought I'd try it. Definite battery savings! But you must follow ALL of the instructions (ie: unmounting the internal HD until you're ready to save). Apple's new "retain RAM disk contents on shutdown" capability and the larger RAM capacities of Wallstreet books makes this a viable option.

Since I'm rarely away from power for too long, I don't have much chance to test the actual savings, however, Macworld claims 'double battery life and triple speed' in RD mode.

Now that RAM is so cheap and G3s can hold a bunch, I was surprised to see your tips with only a passing mention of RAM Disk mode.

MY 3 MINUTE FORMULA FOR A RAM DISK SETUP: - I have a Zip disk on which I keep a dragable, bootable copy of a paired-down system folder and a few app folders. I can simply set up the RAM disk from the Memory control panel, reboot and drag the Zip contents to the new RD partition, set the RD as the startup disk, then reboot once again (& this time booting is way-fast!) -- Now I just make an alias of something on the real HD and put the alias on the RAM Disk (clicking it later will retrieve the unmounted HD), throw the HD icon into the trash to unmount it, force the HD to spin down [cmd-cntrl-shft-zero] and the speed and battery savings are amazing!"

From Aaron Dowler:
"1. Move your trash can to the far bottom left or right of the desktop, when you drag files to it you don't have to be so precise when you're using the not-so-precise trackball or trackpad. For even more easy access to the trash, make an alias of it and put it in both bottom corners.

2. Keep the backlight either off or as low as it can go without being off, with it off, it gives you about 40% more running time, with it down low you get about 15% more.

3. Don't leave telecommunication programs open if you are not using them, your internal modem draws a lot of power.

5. Buy as much ram as you can afford and don't bother with virtual memory -- it's slow and it gobbles up battery power. If you do have to use it, make sure you're plugged in. If you have low Hard Drive space use Connectix Ram Doubler, it doesn't use up Hard Drive space for VM swap files and it is slightly faster than Apple's Virtual Memory (except in OS 8.5)

6. Turn appletalk off in the chooser if you don't use it, it uses extra battery power and slows down the computer.

7. Turn off file sharing, it also uses lots of battery power and slows down the computer.

8. If you have a Powerbook 170 turn on "reduced processor speed" in the powerbook control panel, this will slow the computer down to 16mhz instead of 25mhz, if you are just using a word processor you don't need the extra speed, and this makes a large difference to power consumption, adding an extra 30 minutes (Apple Estimate)

9. Buy Symantec Norton Disk Doubler Pro (used to be Autodoubler, made by some other company) this will give you a little more space (20megs per 80mb of physical HD, aprox) and doesn't slow you down as much as Stacker, Times Two, etc. and it is much safer.

10. Try to run System 7.5.5 or higher, when running system 7.1 on my powerbook 170 I was getting about 45 minutes of battery life, with 7.5.5 I now get about double the battery life and it only uses 300k more ram.

12. If you are on the road and need to print files later, load up print monitor and go to the file menu and choose "stop printing" and the print monitor will act as a printing list, queue the files. When you hook up a printer go back into print monitor and choose "resume printing" from the file menu.

14. Make sure when you are using your powerbook on a flat surface to have the little "feet" down, this helps keep the powerbook from overheating by dispersing the heat better."

From Peter C.S. Adams:
"Add more RAM. The more RAM you have, the less virtual memory is used, conserving power. If you have enough RAM, you can even make a large RAM Disk with a minimal system on it and BOOT FROM IT. This is not only faster, but uses less power.

If your PowerBook has NiMH batteries, make sure to fully discharge them before recharging. "Memory Effect" makes your batteries take less and less charge over time, making it seem that your PowerBook is using more power than it really is.

If it's a Power PC based PowerBook, upgrade to Mac OS 8.6. This version of the Mac OS can increase your battery life as much as 25-35%. (I've seen more modest gains, perhaps because I already use some of the tips you mentioned.)"

From Matt Smith:
"If you hold down the option and command keys while accessing the memory control panel, it shows you a hidden setting - MEMORY STARTUP TESTS. By choosing to turn this off, your Mac won't lose power and time at startup testing each RAM chip. It's especially pertinent if you have a large amount of RAM. There's also a great article in "The Mac Bible" on how to make a RAM disk with everything you need on it..."

From Richard Petty:
"Due to a hardware limitation (one that makes the G3 Series so fast!), you cannot boot to a RAM disk. However, it is still possible to get the savings if you can anticipate how you'll be using you machine. When I'm out with my PB, I'm generally doing research at the library. In this case, I create a Location control panel configuration that disables a lot of stuff in my Extension folder, freeing up some RAM. I've created a RAM disk into which I've copied BBEdit for text editing, Wingz 1.0 for spreadsheet work, and a couple game bargains (MacChess, Othello, etc.) I launch my applications from the RAM disk and tell the hard drive to spin down (Control Strip). At this point, I can spend the entire day working and playing without running the hard disk once. Although I cannot boot my G3 Series PB to a RAM disk, if I can work all day without the hard drive spinning up, what's the difference?!"

Stephen Hildreth has been the Editor-in-Chief of PowerBook Central since its inception in 1996. When not working on his Mac, he shares his love of the outdoors with his family and can be found biking, snow skiing, or educating students on the internal & external processes of our planet.