With RME the "performance" differences between PCI/PCIe/TB and USB/FW are not that big. All RME drivers are written very efficiently and RME does not use third party communication chips on their recording interfaces. RME does everything themselves in their FPGAs. FPGAs are simply said "programmable CPUs" that can be reprogrammed via firmware upgrade regarding bug fixes and feature upgrades. So USB has about the same "performance" as PCI/PCIe/TB.
I checked this myself comparing a PCIe interface (RayDAT) with an UFX+ (USB3) with a very big Cubase Project with 400 tracks and over 800 VSTi (not that I have such large project, I used it as kind of application benchmark for me.
The result was, that there was no real visible difference in "performance", with smallest ASIO buffer sizes and even at double speed (96 kHz):
- about the same CPU load (so the USB Recording interface worked as efficient as the PCIe interface)
- about the same RTL (Round Trip Latency)
https://www.tonstudio-forum.de/blog/ind … cks-de-en/
Additionally you can look at this overview of RTL latencies for example (the snapshot from an Excel), quite similar between the different solutions: https://www.tonstudio-forum.de/blog/ind … 8-RME-UFX/
While you say PCI, you do realize that there are hardly any mainboards with PCI bus anymore ? If you plan to buy such a card, then I would strongly recommend you to get a current PCIe based card.
But I would generally recommend, that you choose a recording interface based on features and supported ports.
For USB/FW/TB cards I put together some interesting information (except PCI/PCIe cards):
https://www.tonstudio-forum.de/blog/ind … B-MADIfac/
Direct Link to Excel: https://www.tonstudio-forum.de/index.ph … 0-08-xlsx/
With PCI/PCIe cards you always have to take into account that you have to deal with breakout cables for many connection types. If you then stumble over something like that, it happens faster that you tear something out. Or if you have pets, such special breakout cables cost just more, than a USB or XLR cable. Or if you want e.g. to have DURec .. not available for PCI/PCIe cards, same with Mic Preamps. Or if you want FX effects, some USB recording interfaces have a FX chip built-in, but not all. If you look at the cards, then only the biggest MADI card has a FX chip..
No RME device is a waste of time or money...
But I ask myself, what is the concrete question / demand behind your posting ? Nice "intro", but for what purpose ?
BR Ramses - UFX III, 12Mic, XTC, ADI-2 Pro FS R BE, RayDAT, X10SRi-F, E5-1680v4, Win10Pro22H2, Cub14