Doom 2016 is one of the most optimized PC games in recent years, pick an AMD card and run the games with Vulkan API, you can easily get > 60 FPS in max settings (1080p).

Intel Core i5 7400 - RM 854
Asus H110M-K - RM 259
G.SKill Aegis 8GB DDR4 2133MHz RAM - RM 255
Sapphire RX470 4GB GDDR5 Nitro+ - RM 998
WD Blue 250GB SSD - RM 413
FSP Hexa+ 550W - RM 195
Tecware F3 - RM 119

Total: RM 3093 (ETECH price inclusive of GST)

To keep below 3k, you can:
1. Downgrade the SSD to other lower end model with either similar capacity or smaller capacity
2. RX470 4GB to RX460 2GB (-40% in performance)
3. Kaby Lake i5 to Skylake i5 6402P (~almost no difference in terms of performance)
4. Further downgrade to i3 7100 (i3 7100 is on par with i5 2400)

BIOS update is required to run Kaby Lake CPU on a mobo with older chipset (H110/B150/H170/Z170).

C-Zone also selling LG 22MP48HQ 21.5" at RM408.
Quite reasonable. You might wanna replace that questionable power supply though.

Because Coolermaster has a crappy line of PSUs. Extreme Power Plus is one of them.

Oh, that chart is just the graphic card, not total system power consumption.