Generate 1000 widget elements - FPS drops to 4-7

If I generate 1000 widget elements W_Elem in GridPanel then FPS drops to 4-7. my PC i7 6 cores 4500Mhz 16gb. How to raise FPS?

What does each widget do? I just changed my inventory window to spawn 1000 slots and it works without an fps drop, except when they are created.

if i use scale box->grid panel, fps down.

I removed the scale box. So far I can cope without this features. Thank you!

Incorrect. Slate/UMG do not cache and update every frame. Volatility does not affect anything unless your widgets are inside an invalidation panel.

Putting a scalebox at the root however can add some overhead as each one requires a second prepass (under non manual scaling configuration) be executed from it on down. So there would end up being a second prepass for the entire grid.

Oh, sorry for the wrong information.