New Build i9 9900k

[Sybex]

Hi everyone, I haven't built a PC in many years and was just wondering on what you guys think of my following build.
Case: Fractal Design S2
Power Supply: Corsair HX850i
Motherboard: Gigabyte Z390 Aorus Pro WiFi
CPU: Intel i9 9700k
CPU Cooler: Corsair H150i
Hard Drive: Samsung 970 Evo Plus 1TB
GFX Card: Gigabyte Geforce RTX2060 6GB Windforce OC
RAM: Corsair Vengeance RGB Pro 16GB DDR4 3200MHz C16 XMP2

I have yet to build this system but have all the parts.
I have a couple of questions if any one can advise.

1, The Motherboard has 2 ATX Power Connectors 1, 8pin ATX and 1, 4 pin connectors, but my power supply does not have the 4 pin 12v connector, does this 4 pin connector have to be used or is this only for over clocking.

2, does this motherboard support the i9 9900k CPU if it come with an early Bios revision.

3, Anyone had any problems with this RAM.

 

[Sybex]

It'll be fine with just 8-pin unless you plan legendary overclocking I would imagine.

Have you just bought these parts? Seems strange to get an RTX2060 6GB when the RTX2060 Super 8GB is much better and similar price.

Unless I'm missing something the Z390 should work out of the box with the 9900K.

It's also a very unbalanced build if gaming is the intention - super high-end CPU, 9900K with mid-range GPU, RTX2060 6GB. Unless you're playing at 144hz and running at lower settings, the CPU will be sitting doing nothing most of the time.

Something like a 9700K/Ryzen 3700X + RTX2070 Super/2080 Super would give much more balanced results.

Thanks for your help Terrorfirmer
The reason on getting the I9 9900k was I got it at a very good price at the time and I may decide to upgrade further when I have a bit more cash, Yes I know its a bit of an overkill.
As for the graphics card, I think I may have made a poor decision