Adding more memory to your PC or laptop is one of the most cost-effective means of boosting its performance. PC Advisor looks at how to choose the right RAM and avoid installation issues.

Now is a good time to upgrade your computer's RAM. Most PCs are sold with 64bit operating systems. Software is more memory-intensive than ever, and 64bit programs and games are shipping. Memory prices have also dropped substantially.

Buying the right memory isn't as easy as it used to be, however. Most current desktop PCs use DDR3 memory, but some older systems use DDR2. The situation is similar with laptops. Check your manufacturer's manual to find out which type of memory you need.
You can also use Belarc Advisor – an online tool that takes an inventory of your setup and suggests suitable components for it. Kingston Technology and Crucial both offer RAM and SODIMM (laptop memory module) upgrade advice, based on the brand and model of your PC.

When upgrading desktop systems, memory speed and timing can be an issue. Many motherboards are unable to simultaneously run modules in each of their memory sockets at full-speed. One strategy is to buy modules a speed grade higher than the motherboard supports, then dial them down. We once ran an X58 motherboard with 12GB of DDR3 RAM; it had six 1,600MHz modules running at 1,333MHz.

Choosing laptop memory modules is a little easier, if you know the rated speed and capacity. Laptop motherboards generally support no more than two memory modules, although a few models have three sockets.

Whether it's a laptop or a desktop PC, a general rule of thumb is to stick to the same capacity for each memory channel. For a dual-channel PC with four memory sockets, for example, it's fine to have two 2GB modules and two 4GB modules. However, you must ensure that each pair of matching modules is installed in sockets for the same memory channel.

Upgrading desktop PC memory

Set the PC on an elevated platform, such as a table or workbench. It's much easier to work inside the case if you have lots of elbow room. Clear all the wiring and clutter from around the DRAM sockets.

Confirm that you have the correct module types for your desktop PC. You don't want to insert DDR3 modules into DDR2 sockets.

Most memory sockets have two locking tabs on either side that flip down to release memory modules for removal. Some motherboards may have a locking tab on only one side. If you're replacing old modules with new memory, unlatch one or both tabs to release and lift out the old module.

Your graphics card or CPU cooling fan may crowd the memory socket to the point that you can't remove or insert memory. In this case, you'll need to carefully remove the offending items first.

Never handle DRAM modules by their gold-plated contacts. When inserting new modules, make sure the locking tab or tabs are completely open.

To ensure you're inserting the new RAM modules the right way round, align the key notch with the corresponding ridge in the memory socket. Be very gentle when inserting new DIMMs. Push the new module straight down into the socket until the locking tabs latch the module into place. Double-check all the tabs are locked and the module is firmly in place.

Reattach any hardware or wired connections you had to remove prior to installing the memory modules.

Now try powering up the system. A succession of fast beeps indicates that one of the modules isn't properly installed or may be defective. If you're trying to fill all the memory sockets, remove the old modules and check whether the PC will boot up properly with only the new ones fitted.

Upgrading laptop memory

It's usually a matter of simply undoing a few screws on the back of your laptop to remove the rear panel and access the RAM. Consult your manual for details of how to open the bay containing the memory sockets. If the manual doesn't explain this, look for the information on the manufacturer's website.

Laptop parts are delicate and very small. You may need to use a screwdriver with a special head to remove the screws from the memory compartment.

Confirm you have the correct module types for your PC (DDR2 or DDR3).
Laptops use SODIMMs, which are smaller than desktop memory modules. Their memory sockets have locking tabs; once unlatched, a spring will often push up the old modules for easy removal.

When inserting a new module, line up its notch with the matching ridge in the memory socket. Slide the module into the slot and press it into the laptop to latch it in place. Check to see whether the system boots up before replacing the compartment cover.

Learn more about your memory

Windows Seizer 1.05 is a useful piece of freeware that displays low-level information about all the windows open on your desktop.

This information includes the window caption, its memory usage, handle, class, parent, process ID and file name, plus the window's size and position.

The initial table displays data on only the windows you can see. Select ‘Show Hidden' and, after a sometimes lengthy delay, you'll also see the many more hidden windows active on your system. This can be useful for developers, but it has more general applications for Windows users, too: if a hidden window keeps locking up or hogging all your RAM, you can spot it here.

As well as watching your system, Window Seizer can also manipulate windows in various ways. It lets you close, hide or reveal windows, terminate locked programs, move them top-left of the screen (this can be very handy if they're currently not visible) and more.

There are a few problems with the program, however. Memory usage doesn't always appear to be reported accurately, for instance. And occasional lengthy pauses sometimes leave you wondering if the program has locked up. Still, Windows Seizer has plenty of useful features and offers a handy way to monitor exactly what's running on your desktop.