Question Upgrade build: From i5-2500k to i7-9700k

[AnUnusedUsername]

Finally looking to upgrade the CPU in my gaming system from an i5-2500k. Unless someone can convince me otherwise, I'm thinking of going with an i7-9700k. What I'm less sure about is the rest of the system, primarily the motherboard. I do not plan on overclocking this time around.

I will need a new CPU, mobo, RAM, and maybe a new CPU cooler and power supply. I plan on reusing the case, video card, hard drives, and peripherals. Budget is flexible, up to ~$1000, less is better. My existing system is at the bottom of this post.

I HATE plastic I/O shields on motherboards. They look tacky and dumb, and I don't want to have a tacky motherboard staring out at me from a nice case. I'll still consider a motherboard that has one, if it can be removed without breaking anything. I care more about longevity than outright performance (hence why I'm considering spending a bit more for a Supermicro board than a high end 'gaming' board).

I'm thinking something like this:
i7-9700k $300 at Micro Center
beQuiet Dark Rock 4 (not the pro, it seems... excessive) ~$75
Supermicro/Supero MBD-C9Z390-CG Motherboard (https://www.newegg.com/p/N82E16813183656) ~$270 at Newegg or $220 at SuperBiiz.
32GB of RAM (https://www.newegg.com/mushkin-enhanced-32gb-288-pin-ddr4-sdram/p/N82E16820226837) ~$130
SeaSonic Foucs Plus 850W power supply ~$130 at Micro Center

Total: ~$850, give or take

So, what did I do wrong with those choices? I realize I probably don't need a new power supply. If 650W can handle an overclocked i5-2500k and R9 290, it should be fine for a stock i7-9700k and the same GPU, but a little headroom for an eventual GPU upgrade is a good thing.

I keep systems for a long time, and plans after the upgrade eventually include a 2560x1440@120Hz monitor and a new video card, so I don't want to hamper that. Usage is 99% gaming, and I play pretty much everything, but mostly RPG, sim racing, and FPS games. I'm not planning on a video card upgrade yet, because I don't see anything drastically better than my R9-290 at a reasonable price.

Here's what I already have:
AsRock P67 Extreme4 Gen3 mobo
i5-2500k @ 4.3GHz
Noctua NH-L12 cooler
8GB DDR3 RAM
R9 290 4GB
SeaSonic x650 PSU
1 TB SATA SSD
500GB HDD
Lian-Li PC-x510WX case
2560x1440@60Hz monitor
My speaker setup requires that the motherboard have an optical SPDIF out (this rules out a lot of otherwise ideal boards).

 

[mdd1963]

9700K is an excellent performer, where gaming results indicate 8 real cores are plenty of CPU power for anything out right now...(get a decent Z390 board, and DDR4 2x8GB/16 GB 3200 MHz RAM kit and you are set, IMO)

Hoping your smallish Noctua can keep gaming load temps down to mid-70C...; if not, if your case will accommodate a taller cooler, I'd look at Noctua's NH-D15 (165 mm mounting height clearance needed)...

 

[AnUnusedUsername]

The L12 came from when I had a smaller case. Spec sheet says up to 180mm will fit this one. I'm thinking of buying the be quiet dark rock 4. I'd like to avoid having something as heavy as the D15 hanging off of the motherboard.

Does RAM speed actually make any difference? It never did in the past. When I built this PC in 2011 the difference between top of the line and bargain-basement RAM was like, 2FPS at best. I don't know if that's still the case but I'd guess that it is.

Finding motherboards that have SPDIF out and don't have an ugly plastic I/O shroud is proving difficult. All the high end gaming boards just look awful. Guess I need to research how hard it is to take one apart...