Do you mean that the CPU usage goes up and the PC responds slowly. If so, this is interesting. This is most likely related to a grphical element causing the system to slow down. The tab control should theoretically take care of this, but about a year ago I ran into a similar situation where a tab caused problem
here. In that case it looked like controls that were partially displayed caused the problem and when using the tab control the problem was there even when displaying another page. If this is so, you can try to determine the source by scrolling the screen in different directions. Once the problematic area is moved off the screen the VI should run faster. This way you can tell which area has the problem.
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