Disabling Onboard Audio Also Disables Soundblaster Card

My current computer setup has two PCI sound cards (a Soundblaster and an M-Audio EMU). I use them both for audio recording. So far, i've had no problems having both of them enabled while the computer is running. Last night, i ran some latency testing and found that my onboard audio driver (portcls.sys) was causing considerable lag when i try to record. After a quick Google search, it seemed that i should have had my onboard audio turned off this entire time, as my Soundblaster is what is running to my speakers.

After going into BIOS and disabling onboard audio, i booted back into Windows. It played the default startup sound, and then, no sound at all. Items would "play" but no sound would come out from the speakers. I went into Device Manager and while the onboard audio device was not listed (which made sense), the Soundblaster and the EMU were both still listed. I tried going into the Sounds option in Control Panel, and while everything still showed that the Soundblaster was my primary audio device, no sound!

Any ideas? Everything points to onboard audio needing to be disabled in order for a PCI sound card to work, but it's completely opposite in my case. As soon as i disable it, all sound devices turn off and i get no sound.