Update README

README.md

@@ -6,6 +6,47 @@ Apollo is a self-hosted desktop stream host for [Artemis(Moonlight Noir)](https:
 
 Refer to LizardByte's documentation hosted on [Read the Docs](https://sushinestream.readthedocs.io/) for now.
 
+## About Virtual Display
+
+> [!WARNING]
+> ***It is highly recommend to remove any other virtual display solutions from your system and Apollo/Sunshine config, to reduce confusions and compatibility issues.***
+
+> [!NOTE]
+> **TL;DR** Just treat your Artemis/Moonlight client like a dedicated PnP monitor with Apollo.
+
+Apollo uses SudoVDA for virtual display. It featurs auto resolution and framerate matching for your Artemis/Moonlight clients. The virtual display is created upon the stream starts and removed once the app quits. **If you couldn't notice a new virtual display being added or removed when the stream starts/quits, then there might be a misconfiguration of the driver or you're still have other presisting virtual display connected.**
+
+The virtual display works just like any physically attached monitors with SudoVDA, Windows will remember the monitor position config natively, there's completely no need for a super complicated solution to "fix" resolutions for your monitors. Unlike all other solutions that reuses one identity or generate a random one each time for any virtual display sessions, Apollo assigns a fixed identity for each Artemis client, or use a dedicated identity each app if using other Moonlight clients.
+
+## Configuration for dual GPU laptops
+
+Apollo supports dual GPUs seamlessly.
+
+If you want to use your dGPU, just set the `Adapter Name` to your dGPU and enable `Headless mode` in `Audio/Video` tab, save and restart your computer. No dummy plug is needed any more, the image will be rendered and encoded directly from your dGPU.
+
+## Troubleshooting
+
+- **No virtual display added**
+  - Ensure the SudoVDA driver is installed
+- **Shows the same screen as main screen**
+  - If you're using an external display for the first time, Windows might configure it as "Mirror mode" by default. Press <kbd>Meta + P</kbd> (or known as <kbd>Win + P</kbd>) and select "Extended", then **exit the app** (not only the stream) and start the app again. You only need to do this once.
+- **Primary display changed to the virtual display after connection. I don't want that.**
+  - Go to Apps and add one entry without any commands. Tick `Always use Virtual Display`, then untick `Set Virtual Display as Default`.
+- **Resolution can't match client side anymore**
+  - ***NEVER*** set screen rotation on virtual displays! Widecar can handle vertical display normally, there's no need to manually set screen rotatition if you're using [Artemis](https://github.com/ClassicOldSong/moonlight-android) with Widecar.
+  - If you happen messed up with your monitor config:
+    1. Disconnect ALL Artemis/Moonlight sessions
+    2. Quit Apollo
+    3. <kbd>Meta(Win) + R</kbd>, then type `regedit`, hit enter
+    4. Delete ALL entries under
+        - `HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\Configuration`
+        - `HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\Connectivity`
+        - `HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers\ScaleFactors`
+
+    This will clear your monitor configuration cache.
+
+    Then you're good to go!
+
 ## System Requirements
 
 > **Warning**: This table is a work in progress. Do not purchase hardware based on this.
@@ -58,6 +99,8 @@ SudoVDA: Virtual Display Adapter Driver used in Apollo
 
 [Artemis](https://github.com/ClassicOldSong/moonlight-android): Integrated Virtual Display options control from client side
 
+**NOTE**: Artemis currently supports Android only. Other platforms will come later.
+
 ## Support
 
 Currently support is only provided via GitHub Issues.