Both monitors are VESA 100 compatible. It's on the spec page for the 32 and in the user guide/elsewhere on the web for the 24.
The 24 is technically not frameless, it just has a very thin top (and perhaps side) bezel.
The 24 is technically not frameless, it just has a very thin top (and perhaps side) bezel.
ftp://ftp.dell.com/Manuals/all-products/esuprt_display_projector/esuprt_Display/dell-u2414h_User's%20Guide_en-us.pdf
Too bad the panel is not a bit nicer...