PS4 Pro's SATA 3.0 connector is kind of a useless upgrade
PlayStation 4 Pro's upgraded SATA 3 standard means very little in the real world.
Sony made the right decision to support the modern, faster SATA 3.0 standard with the PlayStation 4 Pro. Theoretically, this should allow for much faster transfer times on any drive you attach to the console, but it's SSDs that should benefit the most from this.
Faster transfer times are the result faster read/write speeds, which could speed up loading times, and just about every system operation. Well, does it? In the video, Digital Foundry puts this to the test.
The tech outlet attached the same OCZ Trion 100 SSD to the original PS4 and the Pro to find out.
The Witcher 3 is up first, having seen load time benefits through the same upgrade on PS4, does indeed load faster on the Pro, but only by less than two seconds. Fallout 4 only manages to shave one second off the PS4's time, and the same goes for Just Cause 3.
According to the site, we're seeing minimal gains here because developers may have artificially limited the bandwidth used for loading, to leave room for other system processes such as background downloads, instant recording and the like.
Still, there's an obvious advantage over for SSDs standard HDDs, but that's always been the case. The point here is that SATA 3.0 doesn't improve things in any noticeable way.
This could change with future games, however, if developers do account for it, though this is unlikely to happen, outside of edge cases.