Tool
Display advisor
Free to see, Pro to change
Shows how hard WindowServer is working to draw your screens, and offers changes that may give some of it back.
What it does
- Reads WindowServer's CPU, as a share of one core, while the screen is open. If it cannot read it, it says "Unavailable" and shows no number.
- Shows each display's resolution, refresh rate and whether macOS is drawing a larger picture and shrinking it.
- Gives tips only from what it reads: a scaled mode that draws more pixels than the panel has, a refresh rate above 60 Hz on an external display, three or more displays, and Reduce Transparency.
- Try it changes one display's mode. You get 15 seconds to press Keep or Undo; if you do nothing, the old mode comes back.
- After Keep, measures WindowServer for 5 minutes and writes a receipt.
What it never does
- Change anything until you press Try it.
- Make a change permanent. Even after Keep, it holds only until you log out.
- Flip Reduce Transparency for you. That tip opens System Settings.
- Promise a percentage. Impact figures say "up to" and are ceilings, not forecasts.
Free or Pro
The reading and the tips are free. Try it is part of Pro. Undo is never locked.
Honest limits
- Small real drops often read as "No measurable effect" on the receipt. That is the receipt being careful.
- A mode below the panel's own resolution can make text look soft. Hedroom says so on the tip.
- If Hedroom crashes during the 15 seconds, the unconfirmed mode comes back at the next launch or when you log out, not at once.