EDIUS playback performance depends on loaded clip type (resolution, codec, frame rate), project settings, number of video tracks and applied effect.
Playback performance may be less if you add more video tracks. In this case, we recommend render the timeline.

Prerequisite:

1. This knowledge base does not mention about below menu item (red surrounded part)

2. Ensure that Grass Valley HQ standard as render format in project settings. Selected format is used by [Render] menu. If you select another format like long GOP series, using Render menu won’t decrease system load.

 Use Render menu

1. Render selected clip / transitions
Select target clips then select the menu or press Shift + G. 

Rendering is applied to placed clip individually. So, ‘rendered’ is not lost even though moving it to another position.
Below are out of render target:

– Effect that is applied to mixer track
– Audio clip
– Title clip placed onto the T track

2. Render and add to Timeline
When using this menu, all video tracks will be rendered including mixer track (audio and T track are not rendered). Render result will be single AVI file and it will be placed automatically. If you complete editing certain video tracks and you won’t edit furthermore, consolidating the video tracks to single AVI file may be useful to decrease system load.

3. Set as sequence
Select the tracks (video, mixer, T and / or audio) then select Edit > Add Sequence to Bin. Once done, place the sequence onto the timeline then press Shift + G to get rendered single clip