I have actually been thinking about this months, just didnt get to it yet.
I believe you have to specifically detail and pay extra for 'collectables'.
Don't assume your existing policy covers it.
And be clear on covering "replacement cost" and not purchase cost if you can.
I did this with my computer equipment & software 15 years ago, although I didnt have to detail anything, I just went by estimated total value
(heck, cost of all the crap software you buy and dont use really adds up over a decade, you almost wish someone would steal it

).
I think they obsolete equipment on you though, so the closet full of $1000 computers isnt going to cut it.
If you can think of it, they probably have something to cover you.