Enable anti-aliasing in FS2004 (FS9), force it through your graphics driver, and fix jagged edges, shimmer or settings that will not save.
In Microsoft Flight Simulator 2004 (FS2004 or FS9), open Settings > Display, choose the Hardware tab, tick Anti-aliasing, and apply the change. If edges remain jagged, create a graphics-driver profile for fs9.exe and use either Enhance or Override—not a global setting—then test at your monitor's native resolution.
How do I enable anti-aliasing in FS2004?
- Open Display settings. From the main screen, select Settings and then Display. During a flight, open Options, Settings and Display.
- Select the Hardware tab. FS2004 places its anti-aliasing control with the hardware-rendering options.
- Tick Anti-aliasing. Apply the setting and return to the aircraft. It should take effect without restarting, although restarting FS2004 can help if the image does not change.
- Use an appropriate resolution. In full-screen mode, select the display's native resolution where FS2004 offers it. Anti-aliasing cannot fully compensate for rendering at a much lower resolution.
- Inspect a polygon edge. Check a wing, tailplane or building silhouette against the sky. Runway textures, trees and fences may shimmer for different reasons, so they are poor tests of ordinary anti-aliasing.
The built-in checkbox is the safest starting point and does not require driver-specific configuration. Resolution, filtering and mip-map settings also affect image quality; our recommended FS2004 graphics and performance settings cover those related controls.
Which FS2004 anti-aliasing method should I use?
Use FS2004's own anti-aliasing first, then try a per-application driver setting only if the result is too weak or the checkbox has no visible effect.
| Method | Choose it when | Main drawback |
|---|---|---|
| FS2004 anti-aliasing | You want the simplest, most compatible option | Edge smoothing may be modest |
| Driver enhancement | The driver offers an option to enhance application-controlled anti-aliasing | Names and availability vary between drivers |
| Driver override | FS2004's setting is ignored or remains too weak | Legacy DirectX 9 overrides do not work on every driver |
| Supersampling | Transparent objects still shimmer and GPU performance is sufficient | Considerably higher performance cost |
| Post-process AA such as FXAA | Conventional multisampling is unavailable | May blur cockpit gauges and 2D panel text |
Higher sample counts are not automatically better. Stop increasing the setting when wing and building edges look stable at your normal viewing distance; beyond that point, the frame-rate cost may produce little visible improvement.
How do I force anti-aliasing through the graphics driver?
- Close FS2004. Change the driver profile while the simulator is not running.
- Create a per-application profile. Attach it to the actual
fs9.exein the FS2004 installation folder. Do not force anti-aliasing globally, because that changes other programs as well. - Choose a modest multisample level. A 4x option is a sensible starting point where available. Driver panels use different labels, and some no longer expose overrides for older DirectX applications.
- Select the matching control mode. With Enhance, leave FS2004's Anti-aliasing box enabled. With Override, untick the in-simulator box so the driver alone controls the effect.
- Test both display modes. Some driver and Windows combinations apply forced anti-aliasing in full-screen mode but ignore it in a window, or vice versa.
On a laptop or dual-GPU PC, confirm that the profile belongs to the graphics processor actually running fs9.exe. Change one method at a time: combining in-simulator anti-aliasing, an override and a post-process filter makes faults difficult to isolate and can soften the whole image.
Why does FS2004 still have jagged edges?
Persistent jagged edges usually mean the profile is not being applied to fs9.exe, FS2004 is rendering below the display's native resolution, or the visible fault is texture shimmer rather than polygon aliasing.
- Wrong executable profile: make sure the graphics setting is attached to
fs9.exe, not a launcher, installer or shortcut. - Low rendering resolution: select the native display resolution before increasing anti-aliasing strength.
- Unsupported driver override: FS2004 is an older DirectX simulator, and some newer drivers ignore forced anti-aliasing. In that case, use the built-in option rather than repeatedly increasing an override that is not being applied.
- Windowed-mode limitation: compare windowed and full-screen operation if the forced setting appears ineffective.
- Graphics-wrapper conflict: an installed rendering wrapper may control anti-aliasing itself. Avoid making the wrapper, FS2004 and the display driver compete for the same function.
- Transparent textures: trees, fences and some aircraft details use transparency. Ordinary multisampling may not smooth them; transparency supersampling can help where supported, but costs more performance.
- Texture shimmer: crawling runway markings and distant ground textures need filtering and suitable mip-map settings, not simply stronger anti-aliasing.
A mistake we see often is increasing anti-aliasing to cure every form of shimmer. Anti-aliasing smooths geometry edges; anisotropic filtering and mipmapping deal with textures viewed at distance or at a shallow angle.
Why will FS2004 not save the anti-aliasing setting?
FS2004 normally records the display choice in its user configuration, but a read-only configuration file, abnormal shutdown or settings utility can restore the previous value.
- Apply the change and exit normally. A crash or forced termination can prevent FS2004 from writing its updated configuration.
- Inspect the configuration file. Its usual location is
%APPDATA%\Microsoft\FS9\FS9.CFG. Make sure the file is not marked read-only. - Check configuration utilities and presets. Disable anything that rewrites display settings whenever FS2004 starts.
- Rebuild FS9.CFG only as a last resort. Back it up, rename the original and start FS2004 to create a clean copy. This also resets other customised simulator settings.
You should not need to edit FS9.CFG manually just to activate basic anti-aliasing. Once it works, our guide to safe FS9.cfg and graphics adjustments explains which additional changes are useful and which should be treated cautiously.
Does anisotropic filtering remove jagged edges?
Anisotropic filtering does not smooth aircraft silhouettes, aerials or building edges. It keeps runway, taxiway and terrain textures clearer when viewed at an angle, while anti-aliasing handles polygon edges.
If nearby objects look smooth but distant ground textures crawl or become blurred, use trilinear or anisotropic filtering and review mip-map quality. Our guide to choosing anti-aliasing or anisotropic filtering identifies which setting fixes each visual problem.