Could you please try updating via Lifecycle Controller - Unified Server Configurator?
1. Reboot the system
2. Press F10 during POST
3. The Lifecycle Controller GUI should launch
4. Click on Firmware Update (or Platform Update if you are using an older version of LC)
5. If your server is connected to the internet, you could use the FTP option. Or else you can download the DUP and put it on a USB pen drive and select local drive as input.
6. Type in the path to the BIOS 32 BIT Windows DUP and click NEXT.
The system will reboot and flash the BIOS.
Let us know if you still face issues.
Ajay @ Dell