Defective RAM can cause all sorts of problems. If you're suffering from frequent crashes, freezes, reboots, or Blue Screens of Death, a bad RAM chip could be the cause of your travails. If these annoyances tend to happen when you're using a memory-intensive application or game, bad RAM is a very likely culprit.

But that doesn't mean it's a sure one. You still need to make sure that the problem is with your RAM, and if it is, you need to identify the bad module.

The best diagnostic tool I know for the job is the free, bootable MemTest86. Since it's bootable, you need to put it onto removable media. You can download separate versions for installing the program onto a CD or on a USB flash drive.

The CD version comes as an .iso file. The USB version comes with a program that prepares a flash drive, so that it can boot your PC and automatically run MemTest86. If you're not familiar with booting from an optical disc or a flash drive, see Boot discs explained: An overview of booting your PC from something other than your hard drive

How to ease the transition to a new email account

Although that kind of move is a lot easier than moving to a new home, it can still be a hassle. Here are some suggestions for smoothing the process.

1. Don't lock yourself into your ISP's domain. For example, if you're moving from, say, SBC to Comcast, you might be tempted to use your new Comcast email address. That's fine, but what happens if you decide to switch to a different ISP again? You'll face the same hassle all over again.

Instead, start using a Web-based email service you can keep forever and access regardless of who supplies your Internet service. That means Gmail, Outlook.com, Yahoo, or a similar provider.

Learn to build a PC in under two minutes

Building a computer is a great way to get a custom configuration, save some money and have fun. In this how-to video, we'll show you how to build one in less than two minutes.

Google Chrome update: How to access apps and recently closed tabs

Today, Google rolled out a Chrome update that not only relocates that useful option, but also simplifies the browser's new-tab interface.

Let's take a look. In the past, when you opened a new tab (either by pressing Ctrl-T or clicking the new-tab button), you'd see one of two pages: a collection of Chrome apps or a bunch of thumbnails for your most-visited sites.

That was kind of a hassle, having to switch between the two. Now, everything is accessible from a single, more unified, page.

Specifically, when you open a new tab, you'll see the Google Search bar. Below that, your most-visited sites, again in thumbnail form.

As for apps, you can access them by clicking in either of two places. The first is the newly added apps shortcut that was added to your bookmarks bar. (If you don't use that bar, obviously you won't see it.) Clicking that shortcut reveals the old apps screen you're familiar with.

Understanding tech language: The difference between malware and a virus

The word malware (malicious software) describes any piece of code designed to infect your computer (or mobile device) and make it do things that you don't want it to do, such as mass-mail spam or steal your banking passwords. Trojans, worms, and rootkits are all types of malware.

Why you may want a desktop instead of a laptop

Laptops long ago surpassed desktops in sales, and tablets and smartphones are taking major market share from laptops. The tendency is clearly towards smaller, lighter, and more portable computing. But there are some good reasons to stick with a big box that sits on or below your desk.

First off, there's the price/performance ratio. Whether you're spending $300 or $3,000, you will get a more powerful computer for your money if you're willing to give up portability.

Your Twitter account has been hacked! Here's what to do about it

The first thing you need to do is try to log onto Twitter. If you can do that, change your password. This will stop the Twitter thief in his or her tracks, and regain you control of your account--if the thief hasn't already changed the password and locked you out.