OBS projector method

This is the third-choice capture card setup. It adds more delay than Display Clone or Passthrough in our tests, so try those first and use this one when neither works for you. It uses OBS Fullscreen Projector to send the game feed to the capture card, which means your gaming resolution and refresh rate are completely independent from what the capture card receives. You can play at 1440p 480Hz while the capture card gets a clean 1080p 240Hz signal.

Projector vs Passthrough: With passthrough, your gaming monitor is limited to whatever the capture card supports. With OBS Projector, the capture card acts as its own separate display — no limitations on your main monitor. That flexibility is the reason to choose it; the cost is the extra delay.

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#Prerequisites

#Capture Card Requirements

Not all capture cards work well for this use case. Streaming and 2PC AI/color detection are very different workloads. A card that's fine for Twitch streaming may perform terribly here.

What you need:

• A capture card that supports 1080p @ 240 FPS (or at minimum 1080p @ 120 FPS)
• NV12 color format support
• Low latency — budget/generic cards from Amazon often run at 50–60 FPS with high latency, which makes AI detection unusable

Recommended cards:

• Elgato 4K Pro (PCIe) — lowest latency, best option if your Script PC has a PCIe slot
• Elgato 4K X (USB) — very close to PCIe performance, but requires a USB 3.1 Gen 2 or USB 3.2 Gen 2 port
• AVerMedia GC573 / GC553G2 — solid alternatives

USB-C doesn't mean Gen 2. If you're using a USB capture card, verify the port is actually Gen 2. On a Gen 1 port, you'll be stuck at 120 FPS instead of 240 FPS. Check your motherboard specs.

PCIe slot bandwidth matters. If you're using a PCIe capture card, make sure it's in an adequate slot. A PCIe x1 slot may be bandwidth-limited. Check your motherboard manual to confirm the slot speed. If capture FPS is lower than expected, try reseating the card in a different slot.

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#Step 1: Install the Capture Card (Script PC)

The capture card goes in the Script PC — the PC that handles processing and detection. Not the Gaming PC.

1. Install the capture card in the Script PC's PCIe slot (or connect via USB if using a USB card).
2. Update the firmware from the Script PC. Visit the manufacturer's support page (Elgato / AVerMedia / Magewell) for firmware tools and drivers.
3. Reboot the Script PC after updating firmware before continuing.

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#Step 2: Connect the Hardware

1. Connect an HDMI cable from your Gaming PC GPU output → HDMI IN on the capture card (installed in the Script PC).
2. Your gaming monitor stays plugged into the Gaming PC GPU as normal.

The capture card will appear as a second monitor on the Gaming PC.

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#Step 3: Configure the Capture Card Display (Gaming PC)

#Set Windows to Extend Displays

Go to Windows Display Settings and set the display mode to Extend these displays.

Do not use Duplicate. Duplicating forces both displays to the lowest common denominator — this can cap your gaming monitor's refresh rate to whatever the capture card supports. Extend keeps them independent.

#Set the Capture Card Resolution

1. Open NVIDIA Control Panel or Windows Display Settings → Advanced Display.
2. Select the capture card display (it shows up as a second monitor).
3. Set the resolution to 1920×1080.
4. Set the refresh rate to 240 Hz (or the highest your capture card supports).
5. Apply and confirm.

#Verify Active vs Desktop Signal (Important)

This step catches scaling issues. If the active signal doesn't match the desktop signal, Windows is scaling the output, which degrades quality.

1. Go to Windows Settings → System → Display → Advanced display.
2. At the top, select your capture card display from the dropdown.
3. Look at the information shown — you should see both Active signal and Desktop resolution listed.
4. Both should show 1920 × 1080, 240 Hz (or your chosen settings). If they don't match, go back and adjust the resolution/refresh rate until they do.

Where to find this: It's in Windows Settings, not NVIDIA Control Panel. Go to Settings → System → Display → scroll down → Advanced display → select the capture card display from the dropdown at the top. You'll see "Active signal resolution" and "Desktop resolution" listed there.

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#Step 4: Configure OBS (Gaming PC)

#Install and Open OBS

Download and install OBS Studio on the Gaming PC. Make sure your GPU drivers are up to date.

#Video Settings

Navigate to Settings → Video and set:

• Base (Canvas) Resolution: 1920x1080
• Output (Scaled) Resolution: 1920x1080
• FPS: Fractional 240/1
• Color Format: NV12

Why 1080p for capture cards? Unlike NDI/UDP where lower resolutions save bandwidth, capture cards handle 1080p natively without network overhead. 1080p gives better detection accuracy at longer distances since targets are less pixelated. This is the standard setting for capture card setups.

#Add Game Capture Source

1. In the Sources panel, click + and select Game Capture.
2. Set Mode to Capture Specific Window and select your game (must be open).
3. Select the Game Capture source in Sources, then press Ctrl + D to center it on the canvas.

Use Game Capture, not Display Capture. Game Capture is significantly better for performance and quality. Display Capture introduces additional overhead and latency. Only fall back to Display Capture if Game Capture doesn't work with your specific game.

#Set Up Fullscreen Source Projector (Critical Step)

This is how you send the OBS output to the capture card.

1. In the Sources panel, right-click your Game Capture source.
2. Select Fullscreen Projector (Source) → choose your capture card display.

Use Source Projector, NOT Preview Projector. This is a common mistake. Preview Projector can cause the crosshair to appear off-center in the debug view. Source Projector sends the raw game capture directly to the capture card display, properly centered and scaled. If your crosshair is off-center, switching from Preview to Source Projector fixes it.

Can't find the Fullscreen option? The right-click menu just says "Projector" — the fullscreen option is part of the submenu. Right-click → Fullscreen Projector (Source) → select display.

#Disable the OBS Preview

Right-click on the OBS preview area and select the option to disable the preview to reduce GPU usage on the Gaming PC.

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#Step 5: Configure the Application (Script PC)

1. Set Capture Mode to Capture Card in the capture tab.
2. Select the correct capture source/device. If you see your webcam instead of the game feed, you have the wrong device selected — cycle through the available devices until you see the game.
3. Set the capture format to match: 1080p 240 FPS NV12. If this isn't available in the dropdown, use the custom option and enter 1920x1080 @ 240fps (NV12) manually.
4. Load a community config set to capture card mode.
5. Press Start. The debug window should show the live game feed.

Webcam showing instead of game? This means the wrong capture device is selected. Pick the capture card by name in Capture Source. If it is not listed, the capture card may not be plugged in properly or Windows isn't recognizing it.

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#Troubleshooting

#No signal / debug view is black

1. Check HDMI connection. Make sure the HDMI cable goes from the Gaming PC GPU → HDMI IN on the capture card. Not the other way around.

2. Verify the capture card shows as a display on the Gaming PC. Open Windows Display Settings — you should see two monitors. If the capture card doesn't appear, it's not properly connected or recognized.

3. Check that you started the Source Projector. In OBS, right-click the Game Capture source → Fullscreen Projector (Source) → select the capture card display. The projector window should open on the capture card display.

4. Verify display mode is Extend. Duplicate mode can cause issues. Set to Extend these displays.

#Low capture FPS (e.g., 36 FPS when expecting 240)

1. Check the capture card resolution/refresh on the Gaming PC. In Windows Advanced Display settings, select the capture card display. Active signal should show 1920×1080 240Hz. If it shows something lower (like 60Hz), the resolution or refresh rate settings are wrong.

2. USB card on wrong port. If using a USB capture card, verify it's plugged into a USB 3.1/3.2 Gen 2 port. On a Gen 1 port, you're limited to ~120 FPS.

3. PCIe slot bandwidth. If using a PCIe capture card and getting unexpectedly low FPS, try a different PCIe slot. Some x1 slots are bandwidth-limited.

4. Cheap capture card limitations. Generic/budget cards often max out at 50–60 FPS regardless of settings. If your card can't do NV12 at 1080p 240Hz, it may not be suitable. Check what formats and resolutions are actually available in the application's capture settings dropdown.

5. Capture format mismatch. In the application's capture settings, make sure the format is set to NV12 at 1080p 240. If NV12 isn't available for your card, try YUY2 as a fallback.

#Crosshair off-center in debug view

Switch from Preview Projector to Source Projector. Right-click the Game Capture source (not the preview) → Fullscreen Projector (Source) → select capture card display.

#Webcam showing instead of game feed

The wrong capture device is selected in the application. Pick the capture card by name in Capture Source. If it is not listed, the capture card isn't being recognized — check the physical connection and that firmware/drivers are installed.

#Game running in fullscreen causes issues

Some games in exclusive fullscreen mode can conflict with OBS Game Capture or cause the projector output to break. Try running the game in Borderless Windowed mode. OBS Game Capture in "Capture Specific Window" mode generally handles this, but borderless windowed is the safer option.

#Capture backend not working

Moonlight's capture card path is native DirectShow. The older opencv, ffmpeg and libav backend choices were removed, so there is nothing to switch. If the card will not open or shows no picture, close every other program using it on the Script PC (OBS, the card's own software), choose a format the card lists (prefer NV12), then Stop and Start. See Troubleshooting.

#Stuttery aim despite high capture FPS

Capture FPS and detection FPS are different from the debug display FPS. Check all three values in the debug view:

• Capture FPS — how fast frames come from the capture card
• Detection FPS — how fast the model processes them
• Debug display FPS — just the display refresh (cap this at 60 FPS with scale 0.5 to reduce overhead)

If capture FPS is high but detection FPS is low, the bottleneck is your Script PC's GPU or model, not the capture card.

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#Quick Reference