Are you saying the pci express card is a DAC?
Haven't tried that. But I wish I had a different interface from server to dac than USB.
Remember years ago when we were messing with computers and using PCM off the board to connect to the DAC. I got great sound for very little money. A gooe server was $3000. Now the digitql wagon is so so expensive. I observe. But my left, and right brain say no way.
Yes a simple pci express card on the main board ,
PCIe Slots: Everything You Need to Know | HP® Tech Takes
https://share.google/97OUwlfV8exRY1QDX
A simple explanation of it .
Some cards use PCI buss power , some use an additional power source . Like video cards do.
I would not buy a dac card that needs external power . It maybe better but now it's more complex .
Jitter is a made up term to fill the gap of many things.
Not just power supplies,
I think those who use a taiko dac card may have good results
The one thing is isolation from a PC to a dac
Wadax uses a dual optical method this if I'm correct is not just total electrical isolation. It's also a conversion of data and if done well
Aligns the packets timing and has no power needs externally.
Some external dacs don't need power just data
this is I think a better ideal but even in this method there is voltage that is data so jitter in various domains .
Power and timing .
The term daughter cards I think is a PCI express card and it can have a few data outputs
Aes
HDMI / i2s
Spidif and optical
HDMI was never for audio but it does have benefits , not electrical isolation though
A while back there was ideals about controlling the timing of data packets and how much data per packet .
No matter what we do there is conversions and they are math . The math can't be exact so things get changed .
Think having a sacd iso , you still need to convert to play . Well I'm sure as I have heard the methods used sound different.
Now jriver converts on the fly , still something but your iso is left unchanged.