Re: Upgrading Studio Slim 540s
There is one PCI slot on the motherboard, and if it's open you could install a PCI sound card. Since you have an HD3450 it has a PCIeX16 video card slot. I don't know about an upgraded Video card as the power supply may not have enough power as the power supply is only rated at 250 watts (insufficient for many add ons and may even be marginal adding a PCI sound card).
In addition most Dell "S" or compact models require "low profile" type cards. I'm not sure on yours but suspect that is also the case.
What is not compatible on your integrated sound with the Avid Media software, other than there is no System Mixer (what you hear) on new Dell's.
Just a comment, but it looks like the "S" model is not what you should have purchased considering you want to upgrade/add components.
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