Well, there is that general bug with the Intel I225-V Ethernet chip, and my board is definitely affected considering when I bought it.
I had my share of issues with it, too, even on just a 1 Gb/s connection.
There were three revisions of that NIC, and all of them were problematic, but it was worse the older it was. I had the middle one. It was prone to some disconnects early on, and Windows Update was aggressive on pushing driver updates for it (in retrospect, no wonder). Later on, those disconnect issues disappeared, but I still had a consistent issue where whenever I hosted a Minecraft instance from that PC (this could either through single player and using the open to LAN option, or hosting an actual server), then the entire network connection would collapse when another player connected (if it was via open to LAN, it was random when it happened, and if it was a true server, it was instant). Testing using the WiFi or the PC, or various older PCs, were free of the issue. Like, it was wild. Imagine hosting a LAN game and as another player connects to your PC, your NIC decides "I'm going home" and your entire PC loses internet access until you restart the PC. I've almost never heard of that. Unfortunately, no amount of suggested fixes to try in the NIC properties helped one bit.
Looking it up, I eventually found others with different motherboards having the same issue with that game doing that, and they had that NIC in common (the motherboard could vary so it wasn't specific to one motherboard). Those who added a separate dedicated NIC reported success. It became clear what the problem was.
It was bad enough that when I had another issue with that motherboard, I decided to just buy another motherboard, and with a Realtek NIC, instead of waiting on the RMA. It wasn't solely because of this, but it was definitely part of it.
Funny enough the successor I226-V apparently had its share of issues as well. I'll probably be avoiding Intel NICs on my upcoming motherboard purchase after that since it's been too soon. The irony of moving to an AMD platform and the Intel NIC exacts revenge on you!
For games they ( AM4 X3D) is ok, depending on your res, but for everything else they just get slaughtered due to low clocks.
Isn't that a bit of an exaggeration? Outside of games, the difference between the X3D model and the non-X3D counterpart it is based upon is going to be measurable at best, but imperceptible to blindly tell apart in real world use. Contrasted to the difference in gaming, which is larger and far more likely to be felt blindly.
You're basically trading off ~5% "general performance" to move up a whole generation worth in gaming performance. It's a net advantage (you simply wouldn't pay the cost for that difference if you were only doing general tasks that won't benefit from the cache), and that small of a difference is not enough to make it unusable in general tasks. Unless the bare minimum for general tasks is "the fastest that exists", then I don't get why people keep saying this?