I'm just resurrecting this thread after 2,5 years because I've recently stumbled across it since I was looking for a replacement for my TSATA6-PRO-E2 card which was giving me weird problems in my Mac Pro 3,1. On eBay I have found the same exact card that
@trifero is/was selling, i.e. a CALDIGIT cal-85351cb aka FASTA-6GU3 (not the plus or pro version). I was wondering whether or not that particular card is compatible with newer macOS versions and after reading this thread I was unsure. I am happy to report that the card does indeed work with OS X later than Mavericks like the latest Mojave (will test more recent macOS later) even though the
CalDigit website states otherwise. It states:
Upon installing the card in my Mac Pro 3,1, the only part of the card that was recognized were the SATA Ports. System Profiler indicated that the card does feature a USB controller but that there were no drivers installed. I did some googling and I found a driver package for a USB 3.0 ExpressCard that supposedly uses the same Chipset (NEC/Renesas). After installing the package according to its instructions, I had both USB and SATA working. Speed for USB3 and SATA is around 3 Gbit/s which seems about right given the fact that I installed it in Slot 3 of the Mac Pro. I now have a fully functioning Caldigit USB & SATA combo card on Mojave!
I'm actually surprised that it works that well considering the mixed information about the card that is floating around. Just wanted to share this for anyone that might have the same question or same problem with their CalDigit card. Attached you can find a picture of the card I'm using in my Mac Pro and the driver package I've found online. I also attached a screenshot of System Profiler so you can see how the card is recognized in macOS.
Edit: I don't know why the card apparently also has some sort of IDE controller on it? (entry in System Profiler) Either way, the card is functional.