GMOD lags when I start viewing PHX props in the menu

[Invisibleman125]

It says something like "Generated Spawn Icon (139 left in queue)" and it loads a picture for each model and it keeps going until it reaches 0, and then it stops lagging. Did I do something wrong when I installed it, or is this supposed to happen?

(this happens in single player too)

[Teddi]

It's supposed to happen. It's caching the models for future use.