I purchased a Dell XPS 420 desktop a couple of years ago with one of the expressed intents being use as a DVR for security cameras. This required installation of two 4-camera audio/video cards in PCI slots; the only other internal connection required is an audio cable. As per the instructions, I attempted to locate the AUX/CD-in connector on the motherboard. Apparently it either does not exist or I'm too stupid to find it (I am NOT a computer wiz). The next obvious place to look in my mind was the sound card--a Sound Blaster X-Fi Xtreme Music version which Creative Labs tells me is proprietary and made for Dell. Well, believe it or not, no AUX adio input connector there either! At this point the security camera video works great, but no sound and that's something which is critically needed. After-the-fact I purchased a USB microphone and discovered it will not work to record sound based upon how Dell has the motherboard, sound card or both configured! Any help anyone can offer will be greatly appreciated! I'm happy to replace the sound card if that is a fix--especially for the audio-in AUX input. Many, many thanks in advance to you!

A lot of boards don't use CD-In connectors anymore. Audio CD wise, the sound comes digitally down the SATA cable or the IDE cable, therefore CD-In and Aux take-offs are obsolete. Some sound cards do have them still but you won't find them on the cheap-and-cheerful models. Other sound is sent straight to the card via the drivers that power the card so there is no other input for them, it's all digital now.

You can go into the Volume Control, view the Recording properties and change the default input-source since typically by default it'll end up on a channel you'll never use, or if available to a "Mix" or "Stereo" choice so it'll see everything but the exact terminology depends on your hardware.