Why does my computer keep going into standby

it's really simple to fix.

1) Right click your desktop.

2) Select "Properties"

3) A new window will open. Select the "screen saver" tab at the top.

4) Click the "Power" button at the bottom of the window.

5) A new window will open . Change the standby settings to 'Never'.

If that doesn't change anything, I would suggest go to Device Manager, see if there is any problem. If you can't find it out then reinstall your Windows, but before that take the backup of your data otherwise you may lost it. if the backup is not available, then you have to take the help of third party partition recovery tool to recover back the data, which has been lost due to formatting.