Eight tips to start with.

Start with a backup

All PC tweaking begins with a backup, even if you simply create a new restore point. To set one in XP, click Start, Programs (or All Programs), Accessories, System Tools, System Restore, choose Create a restore point, click Next, and step through the wizard. In Vista, click Start, Programs (or All Programs), Maintenance, Backup and Restore Center, select Create a restore point or change settings, choose System Restore, click Next, and then follow the on-screen instructions. (For more information about Windows Vista, you can also read: Vista playing havoc with gamers and Vista and entertainment: The good, the bad and the future.)

Restore points won't solve all your problems. That's why one of the most welcome new tools in Vista is Complete PC Backup, which creates a snapshot of your machine, including all of your applications, settings and data files. Later, if (when?) your hardware fails, you can restore the entire system, not just your files. (Note that Complete PC Backup is not available in Vista Home Basic or Home Premium.)

To create a backup, click Start, Control Panel (or Start, Settings, Control Panel on the Classic Start menu), Back up your computer (in Classic View, double-click Backup and Restore Center). Choose Back up computer and follow the steps. I recommend making a backup at least once per month if you use your PC for work, and a minimum of once every six months no matter how much or little you use it.

Always back up before you make any big changes to your PC's configuration (note that Windows creates a restore point automatically prior to every new software installation and any other significant system change).

Stop unnecessary startups

Whenever you start your PC, various services and programs start up in the background, often without your knowledge. Most of them are programs or services you need, such as your firewall and antivirus software. But some, such as instant messaging apps that you rarely use, do nothing but squander system resources and slow down your PC.

The simplest way to remove the autostart apps you don't use is with the System Configuration utility: Click Start, Run (or just Start on Vista's menu and type in the Start Search box), type msconfig, and press . Select the Startup tab to see the programs that start with Windows. Uncheck those you don't want to run. Next, click the Services tab to see a list of all the services running on your system. Think twice before you uncheck a service, however; many are required to keep your hardware and software operating. The Process Library describes thousands of Windows services and programs, and tells you whether they're necessary. If you're not sure whether you want to run a service or program, enter its name in your favorite web search engine and look in the results for a description.

Keep an eye on performance

The best way to find out how well your system is performing is to run a diagnostics program. The counters in XP's System Monitor utility provide insight into your PC's operation, but they can be difficult to decipher. To run the program, click Start, Run, type perfmon and press . Select System Monitor in the left pane and click the plus sign in the toolbar on the right to add more performance measures.

Vista's Reliability and Performance Monitor is a big improvement over XP's System Monitor. Click Start (or Start, Run on the Classic Start menu), type perfmon and press to open it. The utility is actually several tools in one, but its most useful feature is the Resource Overview, which provides a graphic representation of your current CPU, disk, network and memory use, as well as historical usage stats. The program provides exceedingly detailed information about each measure. For example, in the CPU section you can see every service and application running, how many threads each is using, and the CPU use of each.

Click Reliability Monitor in the utility's left pane to view a day-by-day history of your machine's stability, including itemization of any system crashes and hardware or software failures. You can even drill down for more details about any individual event. The tool also computes an overall reliability index, which changes every day to reflect whether your system or applications have crashed.

Restore files via shadow copies

Another of my favourite new features in Vista Ultimate and Business is Shadow Copies, which backs up your files automatically and makes restoring previous versions of files gone bad a breeze. To revert to a previous version of a file, open Windows Explorer, right-click the file, and select Restore previous versions. Click one of the listed versions to open it.

Keep a couple of things in mind about this feature. First, Vista doesn't maintain a shadow copy of every version of the files you open; instead, each time Vista creates a restore point, it generates a shadow copy. Also, some of the versions you see listed may have been created when you used Vista's Complete PC Backup program.

Tweak your associations

By default, Windows associates certain files with certain programs: when you double-click the file, a specific application opens to run it. But why stick with Windows's choices? To change the program associated with a specific file type in XP and Vista, right-click the file in Explorer or any folder window, and select Open With to produce a list of programs that can run that file. Select Choose Program in XP, or Choose Default Program in Vista. In the resulting dialog box, click the program you want to use as the default, and make sure to check Always use the selected program to open this kind of file. Then click OK. If the program you want to use as the default isn't listed, click Browse, locate and select the program you want, click Open, and then click OK.

Turn on ReadyBoost

One of the simplest and least pricey ways to speed up Vista is by enabling ReadyBoost, which uses a USB flash drive to supplement your computer's RAM. A 1GB flash drive costs as little as $15, and a 2GB device is a little more than twice that amount.

How do you figure the appropriate thumb-drive capacity for your PC? The smallest cache that ReadyBoost can use is 256MB, and the largest is 4GB. Microsoft recommends a flash-memory-to-system-RAM ratio of between 1:1 and 2.5:1. For example, if you have a PC with 512MB of RAM, purchase a flash drive with 512MB to 1.25GB of space. A system equipped with 1GB of RAM should use a drive with a capacity of between 1GB and 2.5GB.

The tricky part involves ensuring that your USB flash drive is ReadyBoost-ready. Be sure to check the minimum requirements and other ReadyBoost information. Before purchasing a specific drive, search the web for information on whether it has been tested with ReadyBoost.

To use ReadyBoost, first plug the drive into a USB port and choose Speed up my system on the screen that appears. On the next screen, select Use this device, and click OK. On the ReadyBoost tab of the device's Properties dialog box, you can either go with the amount of space that Vista suggests reserving for the tool or replace it with an amount you prefer by using the slider control.

Manage partitions easily

Vista's disk-partitioning utility lets you easily create, delete, resize and format partitions. To access these tools, select Start, Control Panel (or Start, Settings, Control Panel on the Classic Start menu), System and Maintenance, and under 'Administrative tools', click Create and format hard disk partitions. (In Category View, double-click Administrative Tools and choose Disk Management in the left pane.) Use the Disk Management menu under Actions on the left to access your maintenance options. You can also right-click an existing partition and select an action from the menu that appears.

Your best bet for managing disk partitions in XP is to use a third-party program such as the US$45 Partition Expert from Acronis.

Generate a one-stop diagnostic report Vista's built-in troubleshooting tool scans your PC, identifies problems and generates a diagnostic report, complete with suggestions for fixing the difficulties. To use it, click Start, Control Panel (or Start, Settings, Control Panel on the Classic Start menu), System and Maintenance, Performance Information and Tools, Advanced tools, Generate a system health report. (In Category View, first double-click Performance Information and Tools, and then click Advanced tools, Generate a system health report.) The system diagnostics utility takes about a minute to run before it issues a report.