You’ve only been burned because you’re cheap – you get what you pay for. Dell’s professional workstations and laptops are rock-solid (optiplex. precision, latitude). And they have fantastic warranties; 3 year pro support is about ~$200 and includes next day parts and installation and the service department is no-nonsense (not that you’ll be needing it much). But that’s nether here nor there. Dell’s biggest money makers are not PCs, they are servers and enterprise infrastructure: switches, routers, SANs, firewalls, SaaS, etc. Dell is the #3 networking provider behind Cisco and HP.
It’s not possible to provide undeniable proof and I think you knew that. You can prove the IP and computer it came from but you can’t really prove who was sitting behind the keyboard. You don’t even need to provide undeniable proof for a murder conviction, or any other crime for that matter. You have to be able to prove beyond a reasonable doubt. That is the principle the justice system is built on.
