When a new computer first arrives, it generally feels snappy, responsive and much faster than your old system.
But, within a few months you might notice that boot and shutdown times are lengthening, applications take longer to load, and your whole system seems a little slower than it used to be. So what's going on?
There are all kinds of reasons why a computer's performance might tail off over time. Many applications install extra components that Windows must load when it starts, for instance, which both extend boot time and consume valuable RAM.
Other programs fill your hard drive and registry with junk files and redundant entries. The more of this clutter you have, the longer it takes to defragment drives, carry out file searches, scan for viruses and more.
On top of this, Windows may simply not be set up properly. Software will sometimes change important Windows settings in a way that cuts performance, without warning – all you'll notice is that your computer feels slower, for no apparent reason.
Don't despair, though. This slowdown isn't inevitable. You can fight back by streamlining Windows, identifying unwanted applications, removing junk files and re-optimising your settings. It's surprisingly quick and easy – Windows provides many tools that can make a real difference, and others are available online, for free.
And streamlining is very effective. When you've finished, you won't just have restored your computer to its original performance levels – it could be even faster.
Unwanted applications
Streamlining starts by taking a close look at the programs on your PC. You might have hundreds of installed applications, for instance, but do you really need them all?
Removing any you no longer need frees up valuable system resources. To begin, click Start ➜ Control Panel, then select Uninstall a program (or Add or Remove Programs in Windows XP). If you have Windows Vista or Windows 7, then right-click the Name column header, click More, and choose the details you'd like to see about each program.
We'd recommend checking the Name, Size, Installed On and Last Used On boxes. Now choose to sort by Date Last Used in Windows XP, or click the Last Used On column header in Windows Vista or Windows 7, and you'll see your applications sorted by when they were last run.
Browse the list carefully. If you've not run something in the last year, say, will you ever want to run it again? If the answer for any program is 'no' then select it, and click Uninstall.
Next, choose Size in the Windows XP Sort box, or click the Size column header to sort your programs by the amount of space they consume, and take a look at the largest. Some games, in particular, can consume a huge amount of hard drive real estate, perhaps 10 or 15GB. Are they really worth it?
If you decide you can do without a particular program, again, select it and click Uninstall. You can also click Turn Windows features on or off or Add/Remove Windows Computers to remove Windows applets you're not using, but this generally has less effect.
If you never run an applet then it won't slow you down, and turning a feature off won't free up much, if any, disk space either.
Pull the plug-ins
Many applications support plug-ins, add-ons or extensions, tiny tools that deliver all kinds of new features and functionality. And this is generally a good thing.
There is a price to pay, though. The more extensions you install, the slower their parent application is to load, the more RAM it consumes, and the greater the chance of instability. So it's wise to review them occasionally, and remove any you no longer use.
In Internet Explorer, click Tools > Manage Add-ons to see the extensions you've installed. If you spot something you're sure you don't need, choose it and click Disable. In Firefox, click Tools > Add-ons > Extensions. Look for add-ons that you no longer use, click them and select Uninstall.
Microsoft Office 2007 comes with many extensions that most people don't need at all. In Office Outlook 2007, for instance, click Tools > Trust Center > Add-ins > Go to see the selection available on your system. If you've installed iTunes, you'll see an iTunes Outlook Add-in and Outlook Change Notifier. These are useful if you want to exchange Outlook's calendar with your iPhone, but if you've no Apple mobile devices, then it's safe to clear the checkboxes to remove them from your system.
You can also clear the Microsoft Office Sharepoint Server Colleague Import Add-in if you don't use Sharepoint Server (if you've never heard of it, you don't, it's a business feature), disable the Microsoft Outlook Mobile Service if you don't send SMS messages from Outlook, and clear Microsoft VBA for Outlook Addin if you're not using Visual Basic for Applications macros. Click OK when you're done, restart Outlook and you should find it loads faster, as well as saving RAM.
Repeat the process in other Microsoft Office tools. In Office Word, for instance, click the Office button, then Word Options > Add-Ins > Go and clear the box next to any toolbars or other options you don't need.
Free drive space
With even budget computers including 1TB hard drives, it's tempting to stop worrying about how your drive space is used. After all, does it really matter whether you've 600GB or 800GB free? The answer, surprisingly, is yes.
Hard drive performance can vary considerably, depending on where your data is stored. Windows stores files on the fastest part of the drive at first, but as you install more applications and create new documents, so transfer speeds for those files drop. The less free hard drive space you have, the slower your PC becomes.
The good news is that you've made a start on improving the situation, by uninstalling surplus programs. And Windows has a Disk Cleanup tool that can help even more, by locating files that can safely be deleted.
Click Start, then Run if you have Windows XP, type cleanmgr.exe and press Return. Choose the drive you'd like to clean, click OK, then wait while Windows scans your PC. When the report appears you'll see a list of file types that can be deleted: thumbnails generated by Explorer, temporary files, the contents of the Recycle Bin and more.
Check the box next to every file type you're sure you don't need, click OK and Windows will delete those files for you.
While this helps a little, specialist drive cleaning tools can find and delete even more redundant files. CCleaner is one of the best.
Defrag properly
As you use a computer, files become fragmented, scattered in chunks all over your hard drive. Windows still loads them correctly, but it takes longer as the hard drive has to move to each piece of the file. Run a defrag tool, though, and it fixes this, defragmenting files into single blocks, then relocating them all to the fastest part of your hard drive.
This can take a long time, sometimes hours, but it's worth it. To get started, click Start > Computer, right-click your main system drive, and select Properties > Tools > Defragment Now. In Windows XP, you can then click Analyze for a report on the degree of fragmentation, or Defragment to defrag right away.
Windows Vista and Windows 7 are a little different. They should defragment your drives automatically, and if that's set up you'll see a message saying that "scheduled defragmentation is enabled". If you don't see this, turn it on by clicking Configure Schedule (Windows 7 only), then checking the Run on a schedule box (Windows Vista and Windows 7).
Even if your drive has been recently defragmented, it's worth doing it again, particularly if you've just uninstalled lots of programs and cleared your hard drive. Click Defragment Now, and leave the tool to do its work. And later, think about trying a third-party defrag tool for even better results. See the 'Defrag your hard drive' walkthrough below for an example.
Windows services
When your system starts, Windows loads many services – background programs that can provide useful functions for the operating system and your applications. Some of these may be unnecessary, though, extending your boot time and wasting resources. Pruning them can offer small performance benefits.
Tweaking services can be very risky, however. If you disable the wrong service then you can crash your computer immediately, and it may not boot next time, either. So if you're a PC novice or at all unsure about how to recover from disasters, skip to the next section.
If you're happy to give this a try, click Start (then Run in Windows XP), type services.msc and press Return to launch the Services applet. Scroll down the list, looking for services you don't need.
If you don't use Media Center, for instance, the Windows Media Center Extender, Receiver and Scheduler services are all useless (these are present in Windows Vista and Windows 7 only, not Windows XP). Double-click each in turn, set their Startup type to Disabled and click OK.
The Distributed Link Tracking Client manages file links over a network. We don't use the feature, you probably don't either. Again, double-click and set its Startup type to Disabled to turn the service off next time.
Other services that can usually be turned off include IP Helper (only useful with an IPv6 network), Offline Files (if you don't use this feature), the Tablet PC Input Service (unless you have a Tablet PC), and the Secure Socket Tunneling Protocol Service (unless you use this to connect to a virtual private network, plugging in to a server at work maybe). And many third-party applications install services you may not need.
Apple's iTunes, for instance, adds Apple Mobile Device and iPod Service, both of which can be turned off if you don't have an iPod or iPhone. The Nvidia Stereoscopic 3D Driver Service can be disabled if you don't have the 3D glasses to take advantage of nVidia's 3D Vision. And if you've installed Nero Burning ROM, but don't use Nero BackItUp, it's safe to disable the Nero BackItUp Scheduler, which may free up a few resources.
Start-up programs
Many applications install components that launch when Windows starts, often without asking. The more you have of these, the longer your computer takes to boot, and the less RAM you have for your other programs.
It's a good idea to streamline your start-up programs list occasionally, to make sure you're only loading software that you really need. This process begins by scanning the icons in your system tray.
Do you see any you never use? If you've installed iTunes, for instance, you may have an Apple QuickTime icon (a blue 'Q'); right-click this and you can launch QuickTime, open recent files and so on. If you find this handy, there's no problem.
But if you never use it, tell QuickTime not to launch when Windows loads. (Right-click the icon, select QuickTime Preferences, click Advanced, clear the Install QuickTime icon in system tray box.)
It's the same story with other icons. If they're from an essential program, like an antivirus tool, or something you use all the time, leave them alone. But if they're surplus to requirements, right-click the icon, and look for a Settings, Options or Preferences dialogue where you can tell it not to launch when Windows starts.
You may have other start-up programs that don't leave icons in the system tray, but these can be viewed from the Windows System Configuration tool. Click Start, then Run if you have Windows XP, type msconfig.exe and press Return to launch this, then click the Startup tab to view your Windows start-up programs.
Scroll down the list, and if you see a program you're sure is unnecessary, clear the box to its left and it won't be loaded when you next boot. Click OK when you're done, then restart your system.
All this streamlining means Windows should boot more quickly, but that's just the start; by freeing up RAM and CPU time, as well as rearranging hard drive folders, your entire system should feel noticeably faster and more responsive.
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