After effects takes too long to render video

I have comps that render at the rate of a few frames a second. I also have comps that take several minutes a frame to render. It all depends on what is going on in the comp. When the render times creeps above a few seconds a frame I use Render Garden, a Background Rendering plug-in, to render a production master and an MP4 preview for the client and my render times drop by about 75%. When my render times start to go longer than three or four minutes a frame I redesign the comp. 

Tell us or show us what is going on in your comps and maybe we can suggest some improvements to your workflow or comp design that will speed things up.

Without any specific info on the contents of the project we can't tell you much, but it seems you have completely wrong expectations and a limited understanding of what AE even is and how it works. Both render times sound perfectly normal and you can do the simple math yourself:

16 seconds at 30 FPS = 480 frames

4 minutes = 240 seconds

240 seconds/ 480 frames = 0.5 sec per frame

How do you expect this to be even faster? Again, I think you need to work on your understanding of AE and its rendering process.

Mylenium

My PC:

Ryzen 5 3600X

RX 580 8GB

16GB RAM