A motherboard can have chips that the operating system does not support. These things need drivers, you know.

There are also things you want support for in the operating system, Windows in this case, but drivers are essential. I have made a motherboard work to 99% with Windows 10 (not my choice of OS for that pc) despite it not having support for 10 by hunting down drivers for each chip from their respective website. That may or may not work. A very new chip is more likely not to have drivers for Windows 7.

only on very rare occasions do you need to update motherboard drivers, ive never updated mine and had no issues

Motherboards don't need drivers per se, but many components do need, including audio, LAN and other stuff. Had a few Pc's that neeed some driver install to work properly, most notably LAN and Audio.
Usually you can get away to not installing every driver missing, like intel storage stuff or chipset drivers. the pc I'm using don't have all the drivers installed and is fine.
Not sure about newer versions of Win7 but some earlier versions didn't support USB 3 out of the box, let alone m.2 storage (in case you eventually need it).

It wasn't a question of whether you need to update them. It was a question of whether you have those drivers in the first place.

Windows and Linux (sorry no knowledge BSD nor MacOS) come with some drivers and they may occasionally work even better for you than what you can download. Nothing more annoying when you only have that one computer and the network does not work but there are drivers for that on a bundled dvd... but you have no dvd driver.

The current consoles have a lot of cores as well, doesn't mean much for PC because of how different the hardware works and PC's much higher clocks. That said there are games already that ask for 8 cores for max settings like Hitman 2, so you never know. No one knows really until a couple years from now.

Worth noting that by that point you could probably get a 3950x for relatively cheap and slot it into the same mobo.

Yes, or something from the next generation (Ryzen 4000). Not too worried and enough for now is enough until I really feel I must have that new game that demands more.

Nice news about the 3950x, just checked a couple of reviews and I'm blown away with the efficiency. Holy crap, it uses rougly the same power as the 3900x 12 core part!

While being a tiny bit slower in some games. Also, not surprisingly it runs out of memory bandwidth with some tasks ('only' dual channel). Nice chip if those two problems do not affect you. The 3900X looks better for gaming on average, partly due to its lower price. Intel's i9-9900KS looks best for gaming, just bring a big watercooler (200W).

This bodes well for the next generation of Threadripper.

I totally get your point and I love games as much as the other guy but in my opinion, "gaming" is a over rated metric to evaluate CPU performance, as we all know, "modern games" run on mostly GPU. By this I mean PC games are designed to max out the GPU, never ever the cpu. Some stuff run on the CPU and can help fps but usually very little.
Anything in ~10% fps is the same in my opinion and if I turned the fps counter off, will never know the difference. Even if there is 10% difference, lowering a graphic setting, will probably do the trick. How many of us can discern "ambient occlusion" on ultra or in high while trying to beat the game?

Regarding price, for a long time the best investment is not on the high end. The last "gaming" pc I built costed nearly as much as the 3950x alone, including a IPS 144Hz monitor, i5 9400f and GTX 1660 Super and it can run games ok :D

Many of us are here for the old games and they run crap compared to today, oh lord, those software controlled mouse cursor wich have like half second lag... We still play them anyway.

Clearly I need sleep!

This is a website that sells games so I thought I would mention the gaming aspect. Does not detract that the 3950X is a ridiculously powerful chip.

At least on my country the value of a 200GE is non existent. The Ryzen 3 1200 cost the same and is a much better chip (no iGPU tough). The ryzen 3 2200G cost 40 euros more, while significant on the whole build is not too much and you get a faster CPU and a much faster integrated GPU.
If you don't plan to use integrated GPU and don't mind Intel look at the i3 9100f, wich tend to be a little faster.
Even the Pentium 5400 is better value than the 200ge, TBH never understand the hype on that chip.

It really depends. CPUs will rarely boost your FPS to any major degree if you have a good video card. Especially at high resolutions. However a weak CPU can absolutely cause you problems on the low end, i.e. poor one percent low performance. For example a lot of very recent games have trouble with 4 core processors causing stutter or low spikes in busy areas for this reason.

In other words I think any Ryzen above a 2600/3600 is just fine for games, unless you're trying to get 240fps in CS:GO. However an old 4 core Intel 6600 or whatever is going to have issues.