Dual GPU & eGPU Setup — Encoder Matrix

Remio Host on Windows enumerates every hardware encoder the system exposes — NVENC on NVIDIA, AMF on AMD, Quick Sync on Intel — and picks the fastest one available, preferring HEVC and stepping up to AV1 when the silicon supports it. On macOS, Remio uses VideoToolbox, which routes through whichever GPU the active display is bound to. Most of the time the auto-selection is correct. This guide is for the rest of the time: gamers who want the discrete card for the game and the iGPU for the encode, creators with a Thunderbolt eGPU, anyone running two GPUs of different vintage.

Overview

You will check which encoder Remio is currently using (Stats overlay in the client), understand which GPUs in your machine actually have encoders (the support matrix below), and learn how to override Remio's default GPU choice when you want a specific card doing the encode. The override is a Windows Settings change for Windows hosts, or a Displays panel toggle for Intel Macs with an eGPU. Apple Silicon hosts route encoding automatically and cannot be overridden.

Prerequisites

Host hardware: a Windows PC with two or more GPUs (discrete + iGPU, dual discrete, or eGPU), or an Intel Mac with a Thunderbolt eGPU. Single-GPU machines do not need this guide.
Remio Host: latest version. Auto-encoder selection has improved across recent releases — older versions may pick differently than this guide describes.
Windows: Windows 10 22H2 or Windows 11 to access the modern Graphics settings page.
macOS: macOS 12 Monterey or later for the eGPU preference toggle. Apple Silicon Macs (M1 and later) do not support eGPUs.
Client: any Remio Client (Mac, iPad, iPhone, Android, Windows) — for confirming the active codec via Stats overlay.

How Remio picks an encoder by default

The selection logic is deterministic and runs once on host startup. The Windows host walks the encoder list in this order:

NVIDIA NVENC — if any NVIDIA GPU with NVENC support is present, prefer it. HEVC primary, AV1 on RTX 4000-series and newer.
AMD AMF — next preference. HEVC primary, AV1 on Radeon RX 7000 (RDNA 3) and newer.
Intel Quick Sync (QSV) — fallback. HEVC primary on Skylake and newer, AV1 on Arc cards and Meteor Lake / Lunar Lake / Arrow Lake iGPUs.
Software encode — if no hardware encoder is available at all, x265 software encode. Rare on any modern PC.

The Mac host has no choice to make on Apple Silicon — VideoToolbox is the only hardware encoder. On Intel Macs with a discrete AMD GPU, VideoToolbox automatically routes encode through whichever GPU the active display sits on. Macs do not expose an explicit encoder switch.

For dual-GPU machines, Remio Host on Windows binds screen capture to the GPU that owns the display being captured (DXGI duplication is per-adapter). The encoder follows: if the display is on the discrete card, the discrete card encodes. If you have one monitor on the iGPU and one on the discrete, switching between them in the Remio client switches both capture and encode to the matching adapter.

TIP
If you want to know exactly what Remio chose, look at the Stats overlay in the client — the Codec line spells it out: HEVC NVENC, AV1 AMF, HEVC QSV, or HEVC VideoToolbox. First token is the codec, second is the encoder.

Encoder support matrix

Which codec each GPU brand can hardware-encode, and which generation introduced support. Remio uses HEVC by default on any encoder; AV1 turns on automatically when both ends support it.

# Hardware encode support by GPU family

VENDOR     ENCODER       H.264    H.265 / HEVC    AV1
-----------------------------------------------------------------
NVIDIA     NVENC         Kepler+  Maxwell 2nd+    Ada Lovelace+
                         (GTX     (GTX 950+)      (RTX 4000+)
                         600+)

AMD        AMF           GCN 2+   Polaris+        RDNA 3+
                         (HD      (RX 400+)       (RX 7000+)
                         7000+)

Intel      Quick Sync    Sandy    Skylake+        Arc / Meteor
                         Bridge+  (6th gen+)      Lake+ / Lunar
                         (2nd                     Lake+ / Arrow
                         gen+)                    Lake+

Apple      VideoToolbox  All      Apple Silicon   not yet (encode)
                         supported all, Intel     decode works on
                         Macs     Macs w/ T2      M3+

# Remio defaults: HEVC everywhere, AV1 if available on both ends

A few important nuances:

NVENC ninth-gen — RTX 4000 and 5000-series cards have dedicated AV1 encode silicon. RTX 4090 has two NVENC engines and runs AV1 at the same speed as HEVC.
AMD AMF on RDNA 3 — the AV1 encoder on RX 7000-series is competitive in quality but slightly slower than NVIDIA's. Still well above 60 fps at 4K.
Intel Arc QSV — Arc A380 and above ship a high-quality AV1 encoder; surprisingly capable for a budget card.
VideoToolbox on Apple Silicon — HEVC is the primary codec on every M-series chip. AV1 hardware encode is not yet exposed by Apple; decode works on M3 and later. Remio uses HEVC on Mac hosts.
Intel Macs with AMD discrete — VideoToolbox uses whichever GPU is preferred for the display. The 16" MacBook Pro 2019 with Radeon Pro 5500M encodes HEVC at 4K60 without breaking a sweat.

Forcing a specific GPU on Windows

Windows 10 22H2 and Windows 11 expose a per-application GPU preference. This is the cleanest way to tell Remio Host which adapter to use on a multi-GPU PC. The setting overrides driver-level defaults and survives reboots.

Open Settings → System → Display → Graphics.
Under Custom options for apps, click Browse.
Navigate to C:\Program Files\Remio\Remio Host.exe and add it. (If you installed Remio Host to a custom path, point there instead.)
Click Remio Host in the list, then Options.
Pick one:
- Power saving — uses the integrated GPU (iGPU). Best for off-loading encode from your discrete card during gaming.
- High performance — uses the discrete GPU. Best when you want NVENC or AMF for AV1.
- Specific GPU (Windows 11 23H2+) — pick by name. Useful if you have two discrete cards or an eGPU.
Click Save, then quit Remio Host from the system tray and relaunch it. The new GPU preference applies on next startup.

The setting also applies to the screen-capture adapter binding, which is the important detail. If you tell Remio to use the iGPU but your monitor is attached to the discrete card, the host has to do a cross-adapter copy of every frame — works, but adds a millisecond or two. For zero overhead, attach the display to the same GPU you want encoding.

NOTE
Remio Host's UI does not currently expose an in-app encoder picker — the OS-level Graphics setting is the supported way to override on Windows. We watch the encoder list at startup, so any changes take effect on relaunch, not while running.

Forcing a specific GPU on macOS

Apple Silicon Macs have a single integrated GPU per chip — no choice to make and no eGPU support. The encode path is fixed and very fast (M2 Ultra encodes 4K60 HEVC in single-digit milliseconds).

Intel Macs with a Thunderbolt eGPU are a different story. macOS lets you mark a specific external GPU as preferred per display, and VideoToolbox follows that preference for any app rendering to that display:

Open System Settings → Displays.
Select the display attached to the eGPU.
Toggle Prefer external GPU on.
Quit and reopen Remio Host. VideoToolbox now uses the eGPU's encoder for that display's stream.

If your Mac has a built-in AMD discrete GPU (Intel MacBook Pro 15"/16", iMac Pro, Mac Pro), VideoToolbox automatically prefers the discrete chip for any display attached to it. The internal display on a 16" MacBook Pro is wired to both the Intel iGPU and the discrete Radeon; macOS routes encode through the iGPU when the laptop is on battery and the discrete when on power.

On Apple Silicon, you cannot force a different encoder because there is only one. This is a feature, not a limitation — the M-series media engine is one of the fastest hardware encoders shipping, and it is shared across all GPU cores transparently.

eGPU specific guidance

External GPUs over Thunderbolt or USB4 add latency you should know about. The full 40 Gbps of Thunderbolt 4 / USB4 is shared between the eGPU command stream, the framebuffer transfer back to the laptop's internal display, and any USB devices connected through the eGPU chassis. In practice:

1-3 ms added latency versus an internal GPU. Negligible for desktop use, slight for competitive gaming.
Bandwidth caps at ~30 Gbps usable (overhead). Enough for any single 4K60 stream. Multiple 4K streams from the same eGPU start saturating.
Display the eGPU output back to the laptop screen — both ways work, but plugging a monitor directly into the eGPU chassis is faster than letting the eGPU push frames back over Thunderbolt to the laptop display. Especially noticeable when gaming locally on the host.
Hot-plug — both Windows and macOS detect eGPU connect / disconnect cleanly. Remio Host re-enumerates encoders on the next session start, so unplugging the eGPU while a session is active will not crash, but the next session may fall back to a different encoder.

For pure encode offload (running a game on the internal GPU, dedicating the eGPU to NVENC), the latency overhead is invisible because the encode happens after the frame is already presented. The frame goes from the internal GPU to the eGPU over Thunderbolt for encode, then back as a tiny compressed bitstream — order of magnitude less bandwidth than the raw frame.

Verifying which encoder is active

The Remio client's Stats overlay is the source of truth. Click the gear icon in the client toolbar, choose Show stats, and look at the Codec line:

# Stats overlay — what the codec line looks like

Codec:    HEVC NVENC           # NVIDIA, HEVC
Codec:    AV1  NVENC           # NVIDIA RTX 40+, AV1
Codec:    HEVC AMF             # AMD
Codec:    AV1  AMF             # AMD RX 7000+, AV1
Codec:    HEVC QSV             # Intel iGPU or Arc
Codec:    AV1  QSV             # Intel Arc, AV1
Codec:    HEVC VideoToolbox    # Mac host
Codec:    H.264 software       # fallback, very rare

The Stats overlay also shows the active resolution, frame rate, bitrate, and round-trip latency. If you tried to force a specific GPU via Windows Settings and the encoder name does not match what you picked, quit Remio Host completely (right-click tray icon → Quit) and relaunch — the encoder enumeration runs once at startup.

For a deeper look on Windows, open Task Manager → Performance and watch the Video Encode graph on each GPU while a session is running. The encoder doing the work shows sustained activity; idle GPUs sit at zero. This is the fastest way to confirm a setting change actually applied.

Troubleshooting dual-GPU sessions

Frame rate drops when a game is running — your discrete GPU is saturated. Force Remio Host to Power saving in Windows Settings → Graphics, restart the host, and the iGPU's QSV takes over. The game keeps the discrete card; encode moves to the iGPU.
Black screen when streaming a fullscreen game — exclusive fullscreen on certain Vulkan and OpenGL titles can confuse screen capture. Fix: in the game's video settings, switch from Exclusive fullscreen to Borderless windowed. Visually identical, but capture sees the surface.
Different displays look different in quality — each display is bound to a specific GPU adapter, and each GPU has its own encoder tuning. Standardize on one GPU (attach both monitors to the same card) for consistent encode quality across the session.
Encoder is HEVC when you expected AV1 — either your host GPU does not have an AV1 encoder (check the matrix above), or the client device cannot decode AV1. Remio negotiates the highest codec both ends support; iPhone 14 and earlier, iPad pre-M3, and many Android devices do not have AV1 decode hardware.
Stats overlay shows software encode — Remio could not initialize any hardware encoder. Common causes: GPU driver is severely out of date, another app has exclusive access to the encoder (OBS in NVENC mode), or the GPU is too old (pre-Maxwell NVIDIA, pre-GCN 4 AMD). Update drivers, close other capture apps, and restart Remio Host.
eGPU disappears mid-session — Thunderbolt cable reseat or sleep cycle. Remio Host needs a restart to pick up the eGPU again. macOS sometimes requires logging out and back in to fully re-attach an eGPU.
Cross-adapter copies showing in Task Manager — the GPU you forced for encode is not the GPU the captured display is bound to. Either attach the display to the encode GPU, or accept the ~1ms penalty of the cross-adapter blit.

FREQUENTLY ASKED

Dual GPU and eGPU questions

Does Remio pick the right GPU automatically?

On most hosts, yes. Remio enumerates every hardware encoder available — NVENC, AMF, QSV on Windows, VideoToolbox on macOS — and picks the fastest one, preferring HEVC and stepping up to AV1 on Ada Lovelace, RDNA 3, or Intel Arc. On dual-GPU laptops it follows the GPU that owns the active display, which is usually correct. You only need to override this when one GPU is saturated by a game or render workload.

What is the difference between NVENC, AMF, QSV, and VideoToolbox?

They are the hardware video encoders built into each vendor's GPU silicon. NVENC is NVIDIA's dedicated encode chip — separate from the CUDA cores, so it does not impact graphics performance. AMF is AMD's equivalent on Radeon cards. Quick Sync (QSV) is the encoder inside Intel iGPUs and Arc cards. VideoToolbox is Apple's encoder shim that talks to the M-series media engine or the Intel iGPU on older Macs. All four produce equivalent H.264 and H.265 output; AV1 support varies by generation.

Can I force Remio to use my integrated GPU instead of my discrete card?

Yes, on Windows. Open Settings → System → Display → Graphics. Add Remio Host.exe (or the executable for whichever host you run), set Power saving, and restart Remio Host. The host now uses the integrated GPU's QSV encoder, freeing the discrete card for your game or render. On macOS the OS makes this choice automatically; you cannot override it on Apple Silicon, but on Intel Macs with an eGPU you can use the Prefer external GPU toggle in Displays.

Does AV1 work on every GPU?

No. AV1 hardware encode is recent: NVIDIA RTX 40-series (Ada Lovelace) and newer, AMD Radeon RX 7000 (RDNA 3) and newer, Intel Arc, and Intel Meteor Lake / Lunar Lake / Arrow Lake iGPUs. Apple Silicon supports AV1 decode (M3 and later) but not hardware encode yet. If your host GPU lacks AV1, Remio uses HEVC instead — same quality, roughly twice the bandwidth.

Does Remio support eGPUs?

On Windows, yes — a Thunderbolt or USB4 eGPU is treated like any other GPU. Force Remio Host to use it via Windows Settings → Graphics. On macOS, only Intel-based Macs support eGPUs; Apple Silicon (M1 and later) dropped eGPU support entirely. Intel Macs with an AMD eGPU work fine for VideoToolbox encode — set Prefer external GPU on the eGPU-attached display.

Why does one of my monitors look lower quality than the other?

Each physical display is bound to a specific GPU adapter, and Remio's screen capture pulls from that adapter's framebuffer. If one monitor is attached to your integrated GPU and another to your discrete GPU, they encode through different chips with slightly different tunings. The fix is to attach both monitors to the same GPU, or accept the small visual difference — encode quality on modern QSV is very close to NVENC for the same bitrate.

Can I run a game on the discrete GPU while Remio encodes on the iGPU?

Yes — this is the most common dual-GPU pattern for streamers and remote gaming. Force the game to High performance in Windows Settings → Graphics, force Remio Host to Power saving, and the game runs full-tilt on the discrete GPU while the iGPU's QSV handles all the encode. Frame timing stays smooth even at 4K60. Pair this with the dedicated NVENC chip on RTX cards (which the game does not touch) and you can keep encode on the discrete card too — pick whichever your hardware likes better.

How do I know which encoder is actually running?

Open the Stats overlay in the Remio client toolbar (gear icon → Show stats). The Codec line shows something like HEVC NVENC, AV1 AMF, HEVC QSV, or HEVC VideoToolbox. The first token is the codec; the second is the encoder. If you forced a specific GPU and the encoder name does not match, quit Remio Host from the tray and relaunch so it re-enumerates devices.