SOTM USB card vs PPAstudio USB Card v2

[shahed99]

I've a question regarding PPA USB card (also applies for SoTM). I don't want to use a PCI/E riser card at all for my music server build. I've heard it might degrade performance.

 

What determines that I can get away without using a riser card? What motherboard/chassis should I use? Does motherboard form factor (micro ATX/mini ITX) matters? Can anyone provide some example build (motherboard/chassis) that didn't require riser card to install PPA usb card? It'd be really helpful to get the info.