Dual monitor Set up Lag

[Juandisimo]

I currently have a 24' Asus VG248 and a 23' VS238 both on a AMD 7950 and my issue is the drop in frames I receive when i have an app running on my 23' monitor while I am gaming on my 24'. I also have my backgrounds on shuffle and when they change my main monitor the VG248 experiences heavy lag/drop in frames. What is causing this issue? I read online that a 144hz and 60hz could work well together but drop in frames is killer when I am gaming.

 

[cdabc123]

2 monitors will ALWAYS be slower then one. the gpu has to work significantly harder.