I’ve been using my new Powerbook with 512 MB of RAM, the pre-installed amount, awaiting the delivery of a new 1 GB RAM module. Just got it this morning, and installed it about an hour ago. Got 1.5 GB of RAM now.

Man, what a difference that makes!

My first test with it was to use Virtual PC, which I could now assign 512 MB of RAM all by itself. With the new 1.67 GHz CPU and max RAM for the app, using Windows XP is damn snappy! On my old TiBook (with half the CPU speed and half the RAM I’ve got now), I used to have to wait several seconds for the screen to redraw and for windows and apps to open. Now using that particular CPU- and RAM-intensive app is much smoother; I almost don’t notice that I’m not using a PC.

Even outside of VPC, I could tell that the memory shortage was slowing me down, causing problems when I had several apps open at once. I knew the extra RAM would make a difference–but was still surprised at how much of a difference it made.

One thing I did notice: Dashboard is eating a lot more memory than it was before. Tiger’s new Konfabulator-like widget module feature used to eat maybe anywhere from 2 MB to 13 MB per widget upon opening, maybe averaging at 3-4 MB each. (Though memory leaks in Dashboard would cause some widgets’ memory allocation to bloat up to dozens of MB each if you left them on long enough.) But after installing the new RAM, tripling my memory, it more than tripled Dashboard’s memory usage. One widget started out eating 30 MB of RAM, and the smallest eater was using 15 MB. Each widget was using maybe 20 MB average.

Not that I can’t afford it now; even with Virtual PC eating up nearly 600 MB or RAM total, and with Dashboard, Safari, and Ecto operating, I still have almost 500 MB of RAM free, almost my total RAM amount before the upgrade. I could open up several more apps before memory started getting tight.

I always tell my students that they should, as a matter of course, buy more memory when they get a new computer, and I’d tell the same to you. Computer makers want to offer you a machine at the lowest price they can, and one of the easiest ways to make the unit seem cheaper is to give you the minimum RAM necessary. 512 MB is quickly becoming the new norm, since 256 MB can’t really cut it so well anymore.

Of course, it’s possible you may not need extra RAM. If you only use one app at a time, if you don’t use RAM-intensive apps, and if you don’t expect to upgrade the OS or apps on your machine for its foreseeable lifetime, then you will probably be happy with what you get at the outset.

Many people are not like that, though. You may play some games with 3-D graphics, you may do photo or movie editing, or you may use apps like VPC. You will probably be opening several applications at the same time. And you will very likely upgrade both apps and operating system at some time, meaning that in a few years, your computer will be eating more memory than it does now; in this respect, adding RAM will effectively extend the lifetime of your computer, allowing you to upgrade farther into the future.

I have a friend who has a 1 GHz Athlon PC running XP. She called me up at one point and told me that she was experiencing a big problem. If she had MS Word only up and running, the computer was fine; but if she opened up another app, like Internet Explorer, suddenly her computer slowed waaay down. I asked her to go to her “My Computer” window, right-click on the icon at the left side of the title bar, select “Properties” from the pop-up menu, and report how much RAM her computer had. Turns out she only had 128 MB of RAM, and that, of course, was her problem.

Extra RAM may add a few hundred dollars to the cost of your computer, but you should see that as a part of the whole price of buying one.