Sometimes, Windows gets confused as to what device it has where and how it should use it. Especially when the motherboard tries to install it (so turn off ESCD if there is a setting in your BIOS). Run through the following actions to force windows to deal with your devices one at a time and assign them unique IRQ's.
Go to start >> control panel >> system >> add/remove hardware
Remove your PCI card, your CD/DVD...
Shutdown.
Physically UNHOOK/Remove each of those things you just uninstalled. Reboot and allow windows to detect that each one of them is removed. Shutdown.
Install/Plug in your PCI device. Boot up. Allow windows to detect and install it. Ensure it is working. Shutdown.
Install your CD/DVD device. Boot up. Allow windows to detect and install it. Ensure it is working. Reboot. Check both PCI and CD/DVD. Ensure both are working.