Some thoughts for you:
I use a the same LG 48" c2 tv.
To run it at 120hz(the max) you need a graphics card with HDMI 2.1 output.
In the nvidia realm which I am more familiar, that is a 3000 series card or better.
And, you want an ultra high hdmi cable.
On the cpu side, consider the types of games that you will play,
If you play cpu centric games, like MMO,strategy or sims, then buy a strong cpu.
Particularly strong in single thread performance.
If you play fast action games, higher resolutions or eye candy then favor a strong graphics card.
Tom's gpu hierarchy chart is a decent guide to comparable gpu capabilities:
We've run hundreds of GPU benchmarks on all the current Nvidia and AMD graphics cards and ranked them in our comprehensive hierarchy.
www.tomshardware.com
I would avoid the cards with maximum factory overclocks; pick an intrinsically stronger base card instead.
Intel cpu option will allow you to use DDR4 ram and motherboards which are cheaper and perform comparably to DDR5.
Intel does not depend on fast ram. 3600 speed ddr4 is fine.
The amd 7800X3d processors looks good for gaming, but they are deficient in any other work. I would be hesitant due to the recent issues with bad voltage destroying the processors.
amd will need ddr5 and performance is connected to the speed of ram.
Intel 13600K/13700K would be a good choice. 13700K is top of the line.
You get what you pay for.
Spend the extra $25 or so for the non F version with integrated graphics.
You will be glad you did if you ever have a gpu issue.
Most any lga1700 motherboard will do, but I would avoid the lesser chipsets like H610.
Pick Z690/Z790/B660/B760.
Modern processors rely on the normal turbo mechanism; overclocking is not usually useful.
What case do you have in mind?
For good air cooling, it should have two 140mm front intakes or 3 120mm intakes to give sufficient airflow to the cpu cooler and graphics card. In coolers, there is nothing better than the noctua NH-D15.
That cooler needs 165mm headroom.
Nothing wrong with over provisioning the psu with 1000w.
A psu only uses the power demanded of it, regardless of the max capability.
DO NOT skimp on quality.
Look for a corsair RMx or seasonic prime/focus with at least a 10 year warranty.