Dell Gaming or Alienware monitors use a standard VESA 100x100 connection. The monitor design allows for seamless installation and removal of the stand (with the stand release button) without any tools such as a screwdriver. This tool less design requires a recess area around the VESA (Figure 1).
Figure 1: Recess Area Around the VESA
Dell offers monitor arms which can be installed without any tools, similar to the monitor stand. Go to Monitor Accessories in the Dell website for more information.
If a third-party VESA mount is used, spacers might be required depending on the size of the VESA adapter plate. Some arms use a small VESA adapter plate which can fit the recess area of the monitor. Other arms use a bigger VESA adapter plate which might need spacers to push the VESA adapter plate out to avoid interference with the housing. Check with the VESA mount vendor for the spacers.