I've recently bought a Dell Inspiron 660 running Windows 8 which has been working well. However, in the last week, it's been randomly switching to just a black screen and no keys / mouse etc have any effect. The only solution is to reboot, which works.

Before you try reinstalling the OS, it might be helpful to do a little troubleshooting to determine if this is a hardware or software problem. Reinstalling Windows means you'll lose all your data on the hard drive, unless it's backed up on external media first.

What I have read online tells me this is usually an ac power adapter problem. I purchased a new Duracell unit yesterday and it still gives the same message. The odd thing is that either my old cord or the new one will charge the battery.