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Spyware, corrupted Windows files, and plain-old poorly written software are all causes of sluggish PC performance. But as you tweak settings, remove software, or reinstall Windows, don't neglect the slowdowns that are due to your PC's hardware. Windows XP and 2000 include tools that help you track down hardware-induced bottlenecks, and a recent update for both those Windows versions makes hardware rehabilitation easier than ever.
Windows' System Monitor program continuously tracks hundreds of performance statistics and records them in log files for more-convenient viewing.
To launch System Monitor in XP and 2000, click Start, Run, type perfmon, and press <Enter>. Choose System Monitor in the left pane, and then click the plus sign ('+') in the toolbar on the right to add more counters that display your PC's performance in real time. Choose a category from the Performance object drop-down menu, select a counter from the list below it, and click Add. Click the Explain button to read a description of the selected counter.
System Monitor's graphs can help you spot trouble areas, but it's best to evaluate your PC's performance numbers over a period of hours or days. Recording this data in a log file is a lot easier now that Microsoft has released the free Performance Monitor Wizard.
RAM: Two useful counters under the Memory object are Available Bytes and Pages/sec. The first displays the amount of physical RAM available to Windows, while the second measures "hard" page faults, which are the times when data had to be swapped between the hard drive's virtual memory and physical memory on the motherboard. If the Available Bytes counter drops below 10 percent of your RAM, while the Pages/sec counter increases significantly, you may not have enough RAM to support the software programs that are currently running on your PC.
CPU: The % Processor Time counter beneath the Processor object measures CPU usage. Software launches and other events may produce a spike to between 90 and 100 percent of CPU capacity, but if this counter consistently measures over 80 percent, your processor may lack the horsepower necessary to handle your system's workload. If your PC has a dual-core CPU, you can select separate counters for each core, or a single counter to measure both.
Hard disk: The % Disk Time counter under the PhysicalDisk object displays the time the hard drive spends reading or writing data. If you have more than one drive, select the drive to monitor. (PCs equipped with multiple striped RAID drives acting as a single volume need to monitor the % Disk Time counters under the LogicalDisk Performance object.) A drive that runs 40 to 50 percent of the time may have to be replaced.