Reader George Robertson wants to give his mate some speed. He writes:

My wife has an iMac from 2010 (model 2389) that she says runs really slowly. I can't afford a new Mac, but as a Christmas present I would like to make this one faster. It currently has 4GB of RAM. Would adding more make it noticeably faster?

That iMac will hold up to 16GB of RAM. These days 4GB is a little light so it's not a bad idea at all to bump up the RAM. However, if you do this on the sly and then expect your wife to burst into the room shouting "George, it's a miracle! My iMac has suddenly turned into a speed demon!" you're going to be disappointed. A RAM upgrade like this does not a miracle make.

If you're looking for the Big Reaction, you want to perform a Bigger Upgrade. And by that I do mean adding an SSD to this computer. Configuring that SSD as the startup drive is the kind of night-and-day difference you're hoping to see. There are a couple of ways you can approach it.

The first is to simply replace the current startup drive. This is fine if your wife hasn't accumulated (or intends to accumulate) a lot of files (or a few really large files). SSD drives cost significantly more money per gigabyte than a mechanical hard drive--between $.55 and $.75 per GB. So to replace a 500GB hard drive you're looking at paying over $300.

The other option is to keep the current drive and slip in another hard drive.

"But hang on," you interject. "I know enough about this computer to understand that it has just one hard drive bay."

Indeed it does. But then there's this: When was the last time your wife used the DVD drive? If your answer is "Oh, that's right, Apple still put media drives on iMacs in those days" then you have your answer. Pull the media drive and replace it with the SSD.

iFixit offers the $40 12.7 mm SATA Optical Bay SATA Hard Drive Enclosure that was designed with exactly this thing in mind as well as instructions for installing it. I've swapped out hard drives in this variety of iMac and while you should be careful, it's not terribly difficult to do.

When performing the operation you'll need a couple of suction cups. You use these to pull the glass display away from the computer. Beyond that you should additionally have a #00 Phillips and a T10 Torx screwdriver on hand.

After you've installed the SSD, either perform a clean install of the Mac OS or, if there's enough room for it, clone her current drive to it using something like Bombich Software's Carbon Copy Cloner. Personally, I'd start fresh with everything and then copy over the data she needs on the startup drive. This will result in a less mucked-up startup drive, which can only help.

Once you've revealed your secret the two of you should discuss where she'll store her data. If you've purchased a smallish SSD--say, 120GB--she'll be better off storing the bulk of her data on the original mechanical hard drive.