1)   BurnInTest Pro 5.0
BurnInTest is an easy to use software tool that simultaneously exercises all major components of a computer, to test for endurance and reliability. Tests include CPU, RAM, disk, video, CD/DVD, printer, serial, parallel, USB, tape and Network.

 2)   ModemTest 1.3
ModemTest performs low level testing of dial up modems and telephone lines. Testing can be done with two modems or a single modem, independent of your ISP. ModemTest logs any data corruption and incorporates a modem speed test.

 3)   PassMark SoundCheck 3.0
PassMark SoundCheck is a Windows based application that allows users to test their PC sound card, speakers and microphone. Verify that your sound card can record and playback sounds at various audio sample rates.