I put together a Brazos based system and one of the things that I wanted to do was omit the standard Switch Mode PSU.
I found a product from Mini-box that is a 80/120 watt variable voltage input DC-DC ATX converter for $55. I decided to power this with a Tripplite PR
-10 Regulated Linear PSU.
Very interesting results vs the standard Switch Mode PSU.
I basically took a TRS to TRS cable, cut it in half and soldered an RCA connector on (Red to tip, black to ground). This means that ground and shield at the TRS end are NOT connected.
Holy cow can you hear a crap load of noise with the Switch Mode PSU, especially mechanical HD seeks. When going to the Regulated supply and DC-DC ATX connector just worlds different.
Now it's fine with a TS-RCA cable, but it was eye opening the difference between the two power supplies. I've always maintained the the largest source of EMI/RFI is from the Switch Mode PSU and this pretty much let me hear what is going on.