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Commands: msconfig

Drivers:

Clean System Directory - 98/etc. - Remove all those stray DLLs from your system.

Driver Sweeper - XP/Vista/etc. - Clean out old drivers to keep your system in tip-top shape.

Hardware:

Belarc Advisor - Vista/XP/etc. - Get a comprehensive report about your hardware and softare setup.

HP USB Disk Storage Format Tool - XP - Format USB Flash Drive and make it bootable (w/ boot.ini, ntldr, and ntdetect).

M2 Information - XP - Free tool scans your system and records hardware specs.

PC Wizard v2005.1.64.3 - XP/etc. - Detect hardware and diagnose PC problems with this powerful utility.

SIV (System Information Viewer) - XP/Vista/etc. - Get a complete rundown about your hardware.

Windows Memory Diagnostic - XP - Check the health of your system's memory.

Performance:

Advanced WindowsCare Personal - XP/Vista/etc. - quick and easy way to juice up system performance.

Everest Home Edition - XP/etc. - Diagnose your OS, and benchmark it, with this utility.
Fresh Diagnose - XP/etc. - Benchmark your PC and check whether it lives up to the manufacturer's claims.

LocalCooling - XP/Vista - Fine-turn your power settings to save electricity.

Network Bandwidth Monitor 2 Lite Edition - XP/Vista - Monitor and graph your bandwidth use.

PC Wizard - XP/Vista/etc. - Tells you everything you ever wanted to know about your PC's configuration and performance.  Everything, that is, except how to fix it.  It is suited for experienced PC users.

ProcessQuickLink - XP/Vista/etc. - Get the latest definitions and exhaustive advice on all the processes running on directly in the Windows Task Manager.

RamBooster - XP/etc. - Optimizes how your computer uses its RAM.

Ultimate Boot CD - Vista/XP/etc. - Run diagnostics from a CD, not from your ailing hard drive.

Remote Control:

CrossLoop - XP/Vista - Access another PC after granted access code with each session.  Clicks the Share tab and reads you the access code listed there, which you type into the client at your end.  It's safe and easy to use for technical support from a remote location.