Update = After verifying ownership and completing troubleshooting, a DELL agent setup a like for like system exchange.
Hi, I got this laptop flickers like crazy when CPU is being utilized, please see the detail below that has been described perfectly on Reddit: XPS 13: Display issue affecting 7390, 9300 and 9310 models : Dell (reddit.com)   Short description of the issue: When the machine is connected to AC without the battery being charged and CPU and RAM are stressed at the same time the display brightness starts to flicker. Turning off turbo boost or limiting cpu frequencies to 3.3Ghz makes the flickering go away. As a consequence the issue does not occur when running on battery because the cpu frequencies are limited there. Disconnecting AC power solves the issue instantly. The flickering can be very subtle as well as very noticeable and according to feedback I got from other users it may be more or less intense depending on the AC adapter you use. This issue is not related to the operating system at all. It was reproduced across different 9310 2-in-1 units in Windows and Linux, as well as with the Diagnosis tool in the Bios (by running the ePSA memory test). In practice (at least with my XPS 13 9310 2-in-1 device) the screen flickering happens at launching applications, loading web pages etc. so it is quite noticeable when doing regular tasks. Additional Notes: When connected to AC power and the battery is being charged, the screen flickering does not happen at all, despite turbo boost frequencies over 4Ghz being reached, so the flickering can be triggered if and only if the laptop is connected to AC power and the battery is not being charged. The flickering happens on all brightness levels, I personally find it easier to see when the display is not too bright. This issue happens with both HDR, PSR and automatic brightness adjustment disabled and no external devices connected. The refresh rate of the display does not have any influence on the flickering. Moving the display does not influence the flickering. Happens with the latest firmware as well (Bios version 2.2.1) The display flickering correlates with coil whine: When the display flickers there is a remarkably different electrical noise being emitted. Every time that characteristic noise kicks in the display flickers for the duration of the noise. Workaround: Disable Turbo Boost in the Bios. Alternatively use the application ThrottleStop to limit the cpu frequency to 3.3 Ghz. Keep in mind, this is not persistent across reboots, so if you want to make this persistent place it in a startup script.   My question is, how do I fix this without disabling the turbo boost?? It made the laptop sluggish!  
XPS 13 9300 Screen Flickering