While the Toughbooks are pretty tough I can't guess how you lost what you have now. For example if you are a student I see them put them into the backpack and hear a thunk as their drop the bag a few inches.
1. There is no NEW laptop for that price in the Toughbook line.
2. There are used Thinkpads that are metal cased and a bit tougher but same LCD so it won't take much more than what broke your HP to break.
I've broken two HP screens with no abuse. I need something a little tougher, I prefer 17 inch, but might consider less if it's a particularly good machine. I don't require a lot of memory.

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