Problems with Davinci

Rencently i have instaled the Davinci software to learn about video editing, but i can use the software cause everytime i try to render some video sample they freeze and i can't watch it at all.
I've already tried install it in 3 diferent desktops: one with AMD RADEON RX480 (4gb) + 16gb ram memory + R7 AMD CPU. Another with NVIDIA GTX 1050 ti graphics + i5 kaby lake cpu and another with GTX 980 + R7 AMD CPU.

In all of them i have the same problem, is impossible to edit any video.

Understand, the software does not lock itself, only when I try to render a video it gets stuck and the frame rate drops dramatically.

Can you help me please?

More details please: footage format and codec, how many effects and/or grades?

What render format? What aspect ratio?

You might try dropping the render speed way down and see if that helps. I have never had to go down to 2fps before, but it is an option. 5fps has generally worked for me on problematic material (including 8K Helium originals). There is a point where you have to get out the hammer and clobber the machine into submission.