I commonly find that assemblies will "lag" when I select more than one component.

By "select more than one component" I mean doing something like Ctrl+click on several components in a row (from the graphics area or feature manager) or using a drag/drop selection box in the graphics area.

By "lag" I mean the cursor will flicker between the mouse -> mouse+circle icons, (indicating that SolidWorks is processing something) and I'll be unable to do anything in SolidWorks until it is finished "doing its thing".

There are some really strange details about this issue, and I'd like to know if anyone else has run into a similar problem.

Details:

-It doesn't happen on all assemblies.

-The behavior is perfectly repeatable- that is, the situation will play out the same every time for a given set of selection inputs (even down to the duration of the lag).

-The lag duration is usually between 7 and 14 seconds.

-I can select any individual component without inducing lag.

-In some cases, I can select two (or sometimes more) components sequentially with no lag (call them C1 and C2). However, if I select a third component (call it C3), SolidWorks will lag. If I select C3 and then C1 and then C2, SolidWorks will lag twice- once when selecting C1 and then again when selecting C2 (in spite of the fact that SolidWorks did not lag when selecting C1 and then C2 previously).

-Once lag is induced by selecting a component, selecting any additional components will cause almost, if not exactly the same amount of lag.

-I can drag/drop a selection box over the whole assembly, and all components are selected with no lag. Using a selection box over certain portions of the assembly induces lag. The situation is similar when using shift-click to select all/a portion of components from the feature manager.

-Lag induced by selecting components from the feature manager is usually more severe than selecting the same components from the graphics area.

-Selecting components during the creation of an exploded view does not induce lag.

**Update 8/9/17

Notably, I've found that Excel might be tied to the issue. Running task manager and observing the processes tab when the lag occurs, I can see that EXCEL.EXE *32 starts using ten times as much CPU as any other process, even though I have no Excel tabs open. The lag stops at the same time that EXCEL.EXE *32 stops using CPU.

Also, the behavior isn't perfectly consistent regarding selection of individual components. I am inducing lag when selecting single components in some cases.

Also, I happen to have SW 2017 installed on the same machine, and even with the same assemblies- I do not experience the issue in that environment.