Does increasing the on-screen size of a transparent quad cost more to render? If so, I wouldn’t consider this a bug. The reason I made this bug report though is because this is causing performance issues at a much lower particle count, somewhere around 300 causing around 18ms Id_Transparent spikes and not all of those particles are near the screen.
Total number of pixels (re)rendered is very important for performance. If you render the entire screen 10000 times, that can easily overwhelm even the fastest GPUs.
While it might be something else, it is hard to know what you are seeing exactly based on just the data in this thread. If this explanation doesn’t help you, please provide a specific simplified reproduction case in form of a rbxl file that shows the problem when ran, and attach it here. Thanks.