I getting hate this device after 3days owning it. The first 1 I bought on Wednesday come with Win8.1. But then after 1 hour use the bottom of the device start to have a bump on an area. I feel weird and today go for 1 to 1 replacement. They replace me a new 1 but only come with win8. They told me it is easy to update to win8.1 just go to the store will do. They say the file is too big so I only can do it at home. Now back home, the device suddenly lag and black screen for 10 minutes after I get into desktop. So I hard press the power button for few times and it finally turned off. I restart again, and yes after a few click on the device it only able to power on. Go to the app store to download win8.1, it keep showing that I am not the admin of device so I am not allowed to download. But weird thing is it showing Win8.1 installing at right top of the store screen. I click in, the win8.1 is downloading but it keep stays at 0%. Anyone can teach me what to do. I already go back to Dell store for 3 times already.