Computer doesn't have video output after changing GPU and PSU

[zivglb]

Hello, I just bought new GPU and PSU and when I connected it to my PC, I could see it turning on (fans are spinning and RGB lights are on) but there was no video output (I tried display port, hdmi, dvi).
I also tried removing the CMOS for 5 minutes but with no success.
I tried also to remove the RAM and the storage to see if they may be causing a short, but I didn’t see results.

Previous setup:
CPU: i7-8700k
Motherboard: asus z 370-f
GPU: 1070ti
RAM: g.skill ripjaws 16X2
PSU: corsair TX550M

I just changed the PSU (Corsair RM750e) and the GPU (4070 ti).

Any suggestions?
Thank you.

[Rustys]

GPU (4070 ti)

Several manufactures for this card need that information as well.

If you totally remove the GPU and attach the display to the onboard, do you get anything?

Prior to replacing the card did you uninstall the previous drivers then insert the card then the drivers?

[Rustys]

Following instruction on other forums closed