Question Upgrading my pc

[F.Demagistri]

Hello,
I wanted to upgrade my pc in order to be able to achieve 144 fps on the monitor pg27uq (UHD 144Hz) and to improve overall performance.
I use my pc for gaming, programming, and 3d modeling (the update is just for gaming purposes, i can model and program just fine with my current pc).
My Current build is :

Case : NZXT 450 ROG NOCTIS
Psu : EVGA SUPERNOVA GQ 1000 W
Motherboard : ASUS ROG STRIX X299-E
Cpu : INTEL I7-7820X
Cooler : NZXT X62 KRAKEN
Ram : GSKILL TRIDENT Z 32 GB
HD : TOSHIBA 2TB SATA 3200 MHz
SSD : SAMSUNG 979 PRO M.2 512TB
Graphic Card : ASUS ROG GTX 1080TI OC 11G
Sound Card : ASUS ROG XONAR PHOEBUS
OS : WINDOWS 10 Pro
Monitors :

• ASUS ROG PG 258Q (FHD 240Hz)
• ACER PREDATOR XB281HK (UHD 60Hz)

This is the build after the upgrade :
Case : NZXT 450 ROG NOCTIS
Psu : EVGA SUPERNOVA GQ 1000 W
Motherboard : ASUS MAXIMUS XI EXTREME
CPU : INTEL I9-9900k
Cooler : NZXT X62 KRAKEN
Ram : GSKILL TRIDENT Z 32 GB
HD : SEAGATE BARRACUDA 4TB 5400 RPM
SSD : SAMSUNG 970 PRO M.2 1TB
Graphic Card : ASUS ROG RTX 2080TI 11G
Sound Card : SOUND BLASTERX AE-5 PE
OS : WINDOWS 10 PRO
Monitors :

• ASUS ROG PG 27UQ(UHD 144Hz)
• ASUS ROG PG 258Q (FHD 240Hz)

Questions:

• Can my case fit this mobo?
• Do you think that with a safe OC i can reach 144 fps on today’s big titles and exploit the 4k 144 Hz?
• If i can afford the pg27uq do you think it s worth?
• Should i wait for the next generation of cpu/gpu to upgrade my pc?
• if no, is there any change you would make to this build?

 

[CountMike]

Hmmmm, what is that you can't do with your PC ?

 

[F.Demagistri]

Hmmmm, what is that you can't do with your PC ?

When i play in FHD on most games i can’t even get 144 FPS, i don’t know if it’s a problem of bottlenecking or what, and when i play in 4k i run at 60 fps with some frame drop, so my question is, if i can’t get 144 fps on a FHD can i get them in 4k?