Low sound volume

I recently bult a PC with an ECS K7S5A motherboard. I disabled the onboard sound, and installed a Sound Blaster 16-bit PCI sound card. Installed Windows XP Pro. Install ran with no problems. When I went to set up sounds for Windows, I could barely hear anything out of the speakers. I adjusted the volume levels to max everywhere I could think of, wihtout much luck. Even tried a different set of speakers. No help. Any suggestions?