# Screen recording: Game Bar, what it cannot capture, and the size problem

> How Game Bar capture works, why some windows record black, and how hardware encoding changes file size and quality.

**Tested on**

- Build: 26300.9457
- Edition: Pro (26H2)
- Architecture: x64
- Evidence: E1
- Verified: 2026-10-29

## The short answer

Game Bar (`Win + G`) records **the foreground app's window**, not the whole desktop, and it uses the GPU's hardware encoder when one is available.

Two consequences:

- **Some windows record black** — apps that render with exclusive-mode or protected output cannot be captured this way.
- **File size is decided by the encoder and the bitrate**, not by the resolution alone.

For a full desktop recording or a window that refuses capture, you need a different tool (OBS-class), not a different setting.

## What it is good at

| Use | Verdict |
|---|---|
| Game clips | good — hardware encode, low overhead |
| Quick demo of one app window | good |
| Narrated tutorial with mic | adequate (mic + system audio) |
| Full desktop, multiple windows | not supported |
| Capturing a protected video stream | blocked by design |
| Long sessions (hours) | file size becomes a problem |

## Recording a clip

1. `Win + G` → **Capture** widget (first use asks to confirm it is a game).
2. **Start recording** — or `Win + Alt + R` for the same thing.
3. Stop the same way. Files land in `Videos\Captures`.

```powershell
# where the captures go and how big they are
Get-ChildItem "$env:USERPROFILE\Videos\Captures" -ErrorAction SilentlyContinue |
  Select-Object Name,@{n='MB';e={[math]::Round($_.Length/1MB,1)}},LastWriteTime |
  Sort-Object LastWriteTime -Descending | Select-Object -First 10
```

## Why a window records black

| Cause | Explanation |
|---|---|
| **DRM-protected output** | the pipeline refuses capture |
| **Exclusive fullscreen** | some games bypass DWM composition |
| **Hardware overlay** | content never reaches the composited surface |
| **A different desktop** | secure desktop, UAC prompt, lock screen |
| **Remote session** | RDP/VM pipelines differ |

Workaround for games: run **borderless windowed** instead of exclusive fullscreen. For protected video, there is no legitimate workaround — that is the point of DRM.

## Size and quality

A rough guide (1080p60, hardware encoder):

| Bitrate | Size per minute | Looks like |
|---|---|---|
| 4 Mbps | ~30MB | acceptable for UI demos |
| 8 Mbps | ~60MB | good for desktop text |
| 20 Mbps | ~150MB | good for fast motion |
| 50 Mbps | ~375MB | near-lossless-ish, large |

Text-heavy desktop content needs a higher bitrate than games to stay readable — the encoder spends bits on sharp edges.

Game Bar exposes quality presets rather than raw bitrate; the presets map to bitrate ceilings. If quality matters, check the recorded file at 100% zoom before publishing.

> **Caution: Recording can capture secrets**
>
> A recording of "just the app" can include notifications, password managers auto-filling, or a second monitor if the tool captures the desktop. Review the file before sharing, and check whether notifications are suppressed during capture.

## Audio

- **System audio** and **microphone** can be recorded together; balance them before recording, not after.
- If the microphone is on a Bluetooth headset, it switches to hands-free mode — you will hear the quality drop in the recording. Use a wired mic.

## When to use something else

| Need | Tool class |
|---|---|
| Whole desktop, multiple windows | OBS-class with display capture |
| Multiple audio tracks | OBS-class |
| Streaming | OBS-class |
| Long archive with chapters | OBS-class + recorder that supports segmentation |
| Very quick clip, single window | Game Bar is fine |

## Related

- [Video codecs: why some files will not play](https://winbook.fyi/en/windows/media/codecs/)
- [Bluetooth audio](https://winbook.fyi/en/windows/peripherals/bluetooth-audio/)
- [Bluetooth audio](https://winbook.fyi/en/windows/peripherals/bluetooth-audio/)

## Lab boundary

E1. Game Bar and Media Foundation capture behaviour is documented by Microsoft/Xbox. The lab VMs have no GPU encoder path, so no capture file was produced.

## Sources

- [Xbox Support — Game Bar](https://support.xbox.com/en-US/help/friends-social-activity/share-social/game-bar)
- [Microsoft Learn — Media Foundation](https://learn.microsoft.com/en-us/windows/win32/medfound/)
- [Microsoft Learn — DXGI](https://learn.microsoft.com/en-us/windows/win32/api/dxgi/)

---

Source: https://winbook.fyi/en/windows/media/capture/