I have an old Dell Dimension 3000 I'm trying to set up as a media server/NAS. I will be installing a PCI DLink gigabit ethernet card. My question is should I disable the onboard sound/video controller to maximize the PCI bandwidth to the ethernet card or will it not make a difference. I plan to remotely manage the server with VPN so I don't need audio/video.
I really doubt that will help the bandwidth at all, since you will not be using them anyway. And if it does, the difference is going to be so small that you would not notice even if you were a robot yourself.
On the other hand by disabling unnecessary resources, you save up on IRQs, avoiding potential problems (conflicts, etc) and a little bit of memory.
Bottom line: disable them and see if everything is alright. If it is, leave it as is. But i doubt you will see any speed improvements.