Thanks for your reply.  I solved the issue by connecting my monitor directly to the onboard display port.  When the monitor was previously connected to the installed RTX 3080, the display would go blank right after starting to boot from the USB Win 11 installation media.  I tried HDMI and DP and had the same issue.  Using the onboard graphics DP port, I was able to install windows to an m.2 nvme ssd.  I did have to switch to AHCI mode for the drive to show up in the win 11 install.  After successfully installing windows and adding the nvidia drivers, I was able to move the monitor back to the RTX 3080 and everything is working.  
The new Dell XPS 8950 will not boot from USB. I have just received my new XPS 8950 and want to do a clean Windows 11 install to a new M.2 NVME drive. However, it does not seem to be possible to boot from a USB flash drive containing the Windows 11 setup media. The Windows 11 USB drive was created using the Windows 11 media creation tool from Microsoft. I have tested it in a different PC to ensure there are no issues with it. When I press F12 for boot options upon bootup, I am able to see the bootable USB drive. When I select it, all I get is a black screen. I have attempted to disable secure boot and updated by BIOS to v1.0.8 (Latest at time of writing) and I also tried all of the different USB ports to no avail.   I also attempted to create a bootable USB drive using MBR instead of GPT however that didn't work as I see no way to switch to legacy BIOS instead of UEFI in the BIOS. I purchased this PC with a 1TB HDD knowing that I would reinstall Windows on a much faster NVME drive. However, as I am not able to bootup to the USB Windows 11 installation media, I cannot install windows to my new fast M.2 NVME drive. I contacted support today and they had me run diagnostics which reported the hardware was healthy. Then they proceeded to transfer me to software support who advised me that there would be a $99 charge to assist me with my issue. Really Dell? If I cannot get this issue resolved soon, I will be looking to return the PC as it is unacceptable to not be able to boot from USB media. Anyone out there dealt with this?
XPS 8950, will not boot from Windows 11 USB