maybe it is the amd processor? have you updated all of your drivers? also there was a cfg file somewhere that you had to replace in order to sauerbraten (I belive sandbox too) not to crash... I´ll look and paste it here if I´ll find
In meantime I recommend to go to sandbox bin folder and apply compatibility mode to all of the exe files, that might fix the problem (Sauerbraten crashed on my computer, after I applied compatibility settings (run as admin and win xp service pack 2) it works fine

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