Hi Sandeep,

With Windows 8+ OEMS change their Boot logo from the standard Windows boot logo so what is really happening is the first one is the BIOS logo, and the second is the now changed Windows Boot logo to the Dell logo. ALL OEMS does this now. Dell, HP, Acer, ASUS, etc.

Unless you wipe and reinstall windows clean from a Windows 10 install disk or USB drive it will always show this for windows boot screen.

If the issue persists then, I suggest you to perform Automatic Repair using Windows 10 installation media. Drivers, conflicts with other programs, malware, and memory can all cause startup problems.

If you don’t have an installation media. you can download and create an installation media of Windows 10 from the below link.

http://www.microsoft.com/en-us/software-download/windows10

Refer to the steps below to perform an Automatic Repair:

1. Insert the installation USB media and boot Windows Technical Preview from it.
2. In the ‘Windows setup’ page select the ‘language to install’, ‘Time and currency format’ and the ‘key
3. board or input method’ and click on ‘next’.
4. Click on ‘Repair your computer’ and select ‘Troubleshoot’.
5. Select ‘Automatic Repair’ and select the operating system.
6. You will then see a blue screen and an option to choose. Choose the option Troubleshoot and select advanced options.
7. You may choose Automatic Repair from Advanced boot option.
8. Follow the instructions.

I hope this helps.

Regards,
Lokesh