I'm hoping this development will add to the consumer switch options as most 2.5gb aren't terribly well priced from the major brands. I ended up getting a switch with 1/2.5/10gb ports rather than getting one all 2.5/10 simply due to the huge price jump.
I didn't get a chance to properly check out the actualy switch stuff at Realtek, as both times I visited, it was really crowded in that area, but I'm going to give it a go tomorrow again. Obviously the PHY is an important aspect as well, as so far, only 2.5 Gbps and below switchings ICs are incorporating an integrated PHY and only one company has announced such a 2.5 Gbps solution. Everything else is at least a two chip solution. The more integrated these things get, the cheaper it gets to produce, to a certain point. However, pricing in every step doesn't have to related to manufacuring cost, so even if it costs someone like Realtek less, they might want to make a larger marging and their customers in turn wants to make a larger margin, which means retail pricing doesn't drop, at least not initially.
And why is that the actual reason for the 5GbE-USB-NIC having USB3.2 10Gb/s instead of 5Gb/s, according to TheLost Swede?
As for the USB to 5 Gbps NIC using 10 Gbps USB 3.2 instead of 5 Gbps, is because 5 Gbps USB isn't really 5 Gbps, as there are overheads. Initially it was marketed as 4.8 Gbps, but got rounded up, but often real world transfer speeds are even slower than that. 10 Gbps USB is using a different data encoding, so it's more efficient, but it still doesn't get you 10 Gbps, but you get closer and the same applies for 20 Gbps USB. So to make sure that the USB interface isn't a bottle neck and with 10 Gbps USB now being a 10 year old standard, I guess they felt pretty safe that anyone that was going to use this product, would have at least one such capable port on their system.
What is the problem with A version?
Im using 8125AG (2.5G) from 2019 and i dont really have to option to "avoid" it. My board also has Intels i211 solution (1G).
So far during these years i have not noticed anything bad with 8125AG.
From what I remember, at 2.5 Gbps speeds, they were having some issues with a lot of older multi-Gig capable switches, so if you're only using Gigabit at home, it shouldn't be an issue to use that NIC. I honestly don't remember the exact issue, but I think that was it and it was fixed in the B version. I believe I have the same chips as well on my board and it has been working fine over Gigabit.
