The Line Attractor node seems to render differently (have different strengths) between Cascade Viewport, Editor Level Viewport, PIE and Standalone/Launched Game
In trying to capture movies for this JIRA, I also noticed that when FRAPS is running and the Framerate drops from 120 to 90, the Particles render as they do in a launched game and Cascade.
The particles also render correctly in the Editor Viewport if Cascade is open and visible (on a second monitor or otherwise)
Also Reproduced in Main-CL-2660934
The Strength of the line attractor module appears to change with the frame rate.
The Strength remains consistent despite variance in frame rate.
RESULTS: The Editor is not correctly previewing the particle system in Editor Viewport
EXPECTED: The particle system should always render the same.
Head over to the existingAnswerHub thread and let us know what's up.