When the product arrived, I didn't have time to use these as I was in the middle of moving.Once I got settled in, I tried to boot these machines. Three of the four I ordered failed with: 3 long beeps and four short beeps. The fourth would not power up at all.I emailed customer service and their response was friendly, fast and most of all solved the issue(s).When I received the computers back, ALL of them worked flawlessly!I would (will) purchase more of these again.