UEFI video resolution
Not sure if this impacts multiple vendors, but Lenovo ThinkPad have this issue. When PXE booting a UEFI enabled system, the video resolution is very low (640x480 or 800x600). This may be a vendor issue, but if there is anything Microsoft can do that would be awesome. Having the resolution so low makes using MDT and other frontends difficult to use as parts of the dialog are off the screen.
Wayne Christopher commented
The resolutions available in UEFI boot are a result of the UEFI video drivers. Those drivers are supplied (as firmware) by either the chipset or GPU manufacturer. There's nothing Microsoft can do about this.