How to record gameplay at constant FPS

Hi, I want to make a demonstrative video of a project , However my PC is not capable to run it on epic settings at a good frame rate.

So I want to record it using the method where no frame is skipped , I don’t remember what was the term for such recording but it worked by taking all the time it took to render each frame during play and in the end you’ll have a recording which will appear to be recorded at constant FPS (30 /60 whatever) even though in reality it took hundreds of milliseconds to render each frame

What was that called Benchmarking? how to do it in ue4?

Create an empty Matinee. When the matinee window pops up, click on the “Movie” button next to “Record”. Set the settings of the video you’ll be recording. When you start recording, it’ll start up the game. Since you didn’t add anything to the Matinee, your game will run as usual. It may lag a lot, but it should be recording everything at the correct fps you had set. It at least worked when I had to put together the trailer for my game.

OK I managed to record an AVI but can’t play it with any of the video players (WMP,MPC,VLC etc) and no video converters recognize it either. Looks like the video file is completely raw and headerless . I also saw a codec field in the movie options box but don’t know what to type in there. What am I doing wrong?

Nevermind I figured it out you have to end game first using Alt+f4 or escape or whatever works but DO NOT press stop recording. Instead exit the game in the new window and it will tell you recording finished.