Problem: No sound from the speakers.
Diagnosis 1: Speakers disconnected.
Solution: Check cables to see if speakers are plugged in. If they are, verify that everything is plugged in correctly.
Diagnosis 2: Sound muted or set to lowest setting.
Solution: Windows should have a little yellow speaker icon on the taskbar, near the clock. If there is a red circle with a slash through it over the icon, the speakers are muted. Double-click on the icon, and in the window that shows up, there will be a box with a check in denoting muted sound. If the speakers are not muted, you can still double click on the speaker icon and check the volume setting (just worry about the volume control all the way on the left).