Question Computer sometimes after switch on or reboot no screen but the pc is on

[Selynelar]

Good day All,

My problem is that sometimes when I start my computer no display and sometimes also on my keyboard and my mouse the lights not turn on. Sometimes happens also after reboot.
When I press the main power button to turn off the computer when it happens. And after when I turn on again it works without any issue.
I also realized that when I turn on the computer it looks like slowly get power the monitor and kb/mouse as well.
Fast boot is off in bios. Fast startup is also disabled in power options. Could be these settings to effect the mentioned issues?
This one happened sometimes with my previous config as well.
What can be the problem? Almost everything is brand new( i bought like in one year them) and I tried to build my pc only from the best quality components.

My pc specs are:

Cpu/Cooler: I7 10700K/Noctua NH-D15 ChromaxBlack
Motherboard: MSI Z490 UNIFY
Case: BE QUIET PURE BASE 500DX
Gpu: MSI RTX 3080 GAMING Z TRIO - all 3 pcie connections connected seperately/ newest driver installed
SSD: Samsung 970 EVo Plus 1TB M.2 Pcie Nvme
RAM: HyperFury 2x16GB 3200mhz
PSU: Seasonic Focus Plus 850W Platinum
CASE FANS: 3xBe Quiet Silent Wings 3 (3pin) 14cm Fan
DISPLAY: ACER XB273UGS

Thanks for your replies.

 

[Ralston18]

Perhaps something has come a bit loose over time.

The first power up attempt fails but warms up the system enough to cause expansion somewhere tightening a connection. The second startup then succeeds.

= = = =

Power down, unplug, open the case.

Clean out dust and debris.

Verify by sight and feel that all connectors, cards, RAM, and jumpers are fully and firmly in place.

Inspect for signs of damage: melting, bare conductor showing, pinched or kinked wires, swollen components, browned or blackened areas, loose or missing screws.....