The smaller iMac gets a 4K display, all the 27-inch models have 5K
Dana Wollman / Engadget :
Context & Ripple Effects
The 21.5-inch iMac's move to 4K was well-trailed — 9to5Mac reported in early September that the smaller iMac would get the higher-resolution panel and ship by November — so today's announcement lands on schedule rather than as a surprise. What rounds out the refresh is that every 27-inch model now carries a 5K screen by default, meaning high-density displays are no longer a top-tier option but the baseline across the line.
The groundwork for this was software-side: OS X gained support for single-stream 4K monitors and third-party 5K panels like Dell's earlier this year, per the 10.10.3 update, which made driving these resolutions from an iMac practical. The question reviewers are now asking is whether the new screen justifies the price — Ars Technica's hands-on of the 4K Retina iMac finds same design, new insides, better display.
First-order effects
- Buyers choosing the $1,499 21.5-inch model now get 4K standard, while anyone configuring any 27-inch iMac gets 5K regardless of trim — resolution is no longer a differentiator within either size class.
- Third-party monitor makers like Dell lose the resolution advantage they had held over Apple's all-in-one since OS X added support for their 4K and 5K panels.
Second-order effects
- With 5K now baked into every large iMac, Apple controls both ends of the desktop-display market — integrated and standalone — which foreshadows its later entry into external displays with the 27-inch Studio Display.
- Windows PC makers face pressure to match retina-class densities at mainstream prices, since Apple has pushed 4K down to the entry point of its desktop line.
Third-order effects
- If high-DPI becomes table stakes across desktop computing, display panel quality shifts from a spec-sheet differentiator to a supply-chain cost every vendor must absorb — and Apple's control over scarce 5K panel production becomes a durable moat, as the seven-year gap before it offered a comparable standalone display suggests.
- The pattern points toward operating systems and GPUs being built around high-resolution output first — a trajectory visible when Apple's own laptops began touting multi-4K/multi-5K drive capability the following year.
The trend: Desktop computing is consolidating around high-density displays as default hardware rather than premium options, with Apple using panel supply to define the category's floor.