Re: 2 questions one thread
You have to reroute the sound through the card for the HDMI to deliver it to the TV or monitor with sound.
Right click the speaker icon in the tray and select playback devices. When the window opens you'll see where the sound is being routed now. If you see your TV on the list then select that as the primary playback device. Click apply then ok.
When I change the selection I normally reboot then go back to make sure my selection was locked in.
As for the dell MB, the ones I've seen have the holes for the hold down screws in odd places that don't mate up to other MB mounting plates. When you're looking at the case from the front, does the right side open up to get in to the insides?