MUX Switch and Advanced Optimus Explained (Force the dGPU)
By Tier1Settings Updated Published
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A MUX switch lets a gaming laptop send frames from the discrete GPU straight to the screen instead of copying them through the integrated GPU first, which gains FPS and cuts a little latency; Advanced Optimus is NVIDIA’s version that switches automatically without a reboot. On an Advanced Optimus laptop the choice is the Display Mode setting in the NVIDIA Control Panel: Automatic Select, Optimus (integrated GPU drives the screen) or NVIDIA GPU only (discrete GPU drives it). On other MUX laptops it’s the GPU mode in your vendor app or BIOS.
If your laptop has a powerful discrete GPU but games feel slower than they should, there’s a good chance your frames are taking that detour. Removing it is one of the biggest free FPS gains on a gaming laptop.
Every frame your discrete GPU renders has to reach the display. The shortest path is the fastest one.
The problem: Optimus routes around your best GPU
To save battery, NVIDIA Optimus (and AMD’s equivalent) wires the laptop display to the integrated GPU. When you game, the discrete GPU renders the frame, then copies it over to the integrated GPU to actually display it. That copy step costs performance and adds a little latency every single frame.
The fix: a MUX switch
A Multiplexer (MUX) switch is hardware that lets you reroute the display directly to the discrete GPU, cutting the integrated GPU out of the chain entirely. How much FPS that buys depends on the game and the laptop: ASUS measured an average of about 9% across its own tests when ROG laptops switch to the dGPU-only (MUX) mode, with outliers such as Rainbow Six Siege gaining more than 30%. Independent tests have found much smaller gains on some laptops, close to zero where the game was limited by something other than the copy step. High-frame-rate competitive games tend to gain the most, because the copy cost repeats on every frame.
The catch: a classic MUX switch requires a reboot to change modes.
Advanced Optimus: the automatic version
NVIDIA’s Advanced Optimus is a smarter MUX. It switches the display between integrated and discrete GPU automatically and without a reboot, giving you discrete-GPU performance when gaming and integrated-GPU battery life otherwise. If your laptop supports it, it’s the best of both worlds.
Display mode: Automatic Select vs Optimus vs NVIDIA GPU only
On laptops with Advanced Optimus, NVIDIA’s Control Panel has a Display Mode setting with three options, on the page labelled Manage Display Mode or Manage Power and Display Mode depending on the driver. NVIDIA’s own definitions:
| Display mode | What drives the laptop screen | Best for |
|---|---|---|
| Automatic Select (default) | Switches to the discrete GPU when a game on NVIDIA’s allow list launches, and back to the integrated GPU a few seconds after the last one closes | Most people — gaming plugged in, battery life otherwise |
| Optimus | Always the integrated GPU, whatever is running and whether you’re on battery or AC. The discrete GPU still renders games and copies frames over, as on a standard Optimus laptop | Battery life, travel, light work |
| NVIDIA GPU only | Always the discrete GPU, whatever is running and whether you’re on battery or AC | Gaming plugged in when you want the switch guaranteed |
When Automatic Select won’t switch to the discrete GPU. NVIDIA lists these cases: the laptop is on battery, an external monitor is connected, an external GPU is connected, or the game (or another running app) is DirectX 9. If any of those apply, pick NVIDIA GPU only instead, or add the game under Manage 3D settings → Automatic Display Switching (Global or Program Settings), which is where NVIDIA’s allow list is edited.
What switching looks like. The screen can freeze for a few seconds while ownership changes — that’s expected, and it can take longer on Windows 11. Windows’ Display settings will then show two displays: the discrete GPU’s panel as display 2 (active) and the integrated GPU’s as display 1 (disabled). NVIDIA also warns that a running DirectX 9 app can crash or freeze if you change the display mode while it’s open.
“Manage Display Mode” missing? The page only exists on laptops that can switch the screen to the discrete GPU. On a standard Optimus laptop the internal panel is wired to the integrated GPU and no setting changes that — only external monitors plugged into a port wired to the discrete GPU skip the copy. Some laptops with Advanced Optimus need it enabled in the BIOS first: Razer’s instructions are BIOS → Chipset → GPU MODE → NVIDIA Dynamic Display Switch, then restart.
How to force the discrete GPU
The exact wording depends on your laptop brand, but the setting lives in the vendor app:
- ASUS → Armoury Crate → GPU Mode → Ultimate (dGPU) / Standard (hybrid)
- Lenovo Legion → Legion Vantage / Legion Space → GPU Mode → Discrete / Hybrid
- MSI → MSI Center → GPU Switch → Discrete GPU
- HP Omen → Omen Gaming Hub → GPU settings
- NVIDIA Control Panel → on Advanced Optimus laptops, Display Mode → NVIDIA GPU only (see the table above)
Set it to the discrete/dedicated option, reboot if prompted, and game plugged in (forcing the dGPU drains the battery fast — see laptop power settings).
Verify the integrated GPU is out of the chain
- Open NVIDIA app / Control Panel while a game runs and check the GPU activity, or
- Use an FPS/hardware overlay such as MSI Afterburner to confirm the discrete GPU is the one under load and driving the display.
If you’re still not getting expected FPS afterwards, rule out other causes with our bottleneck guide and a clean driver install.
When hybrid mode is actually fine
If you’re away from a charger and just browsing or doing light work, hybrid/integrated mode is the right call — it dramatically extends battery life. Save discrete mode for when you’re plugged in and gaming, or let Advanced Optimus handle it for you.
Stack the free wins
Forcing the dGPU is a free FPS gain; the timer is a free latency gain. Pair this with the Windows timer resolution tweak via Tier1Suite and proper FPS capping for the smoothest possible feel from your laptop.
Related guides
- Gaming Laptop Optimization Guide
- Best Windows Power and Battery Settings for a Gaming Laptop
- How to Show an FPS Overlay in Any Game
- How to Clean Install GPU Drivers With DDU
- How to Check for a CPU or GPU Bottleneck
A MUX switch sends frames straight from your discrete GPU to the screen instead of detouring through the integrated GPU, gaining FPS and cutting latency for free. Enable it in your vendor app, reboot, game plugged in, and verify the dGPU is doing the work.
Frequently asked questions
Does a MUX switch increase FPS?
Usually, but by how much varies. A MUX switch routes the display straight from the discrete GPU instead of copying every frame through the integrated GPU. ASUS measured an average gain of about 9% on ROG laptops, with Rainbow Six Siege gaining more than 30%, while independent tests have found little or no gain on some laptops. High-frame-rate competitive games benefit most.
How do I know if my laptop has a MUX switch?
Check your laptop's vendor app (Armoury Crate, Legion Vantage, MSI Center) for a GPU Mode, Display Mode, or Discrete GPU option. If you can set it to dedicated or discrete GPU only and it asks you to reboot, you have a MUX switch. If there is no such option, your laptop likely lacks one.
What is the difference between Optimus, MUX, and Advanced Optimus?
Standard Optimus always routes the display through the integrated GPU to save battery, costing some FPS. A MUX switch lets you manually route the display to the discrete GPU but requires a reboot to change. Advanced Optimus (NVIDIA) does that switching automatically and without a reboot.
Should I set the NVIDIA display mode to Optimus or NVIDIA GPU only?
On a laptop with Advanced Optimus, NVIDIA GPU only puts the internal display on the discrete GPU all the time, which is the most consistent choice for gaming while plugged in. Optimus keeps the display on the integrated GPU and copies frames over, which saves battery but costs some FPS. Automatic Select, the default, switches to the discrete GPU only when a game on NVIDIA's allow list launches and you are on AC power with no external monitor connected.
Why is Manage Display Mode missing from the NVIDIA Control Panel?
The display-mode page only appears on laptops whose display can be switched to the discrete GPU, through a MUX switch or NVIDIA Advanced Optimus (also called DDS, Dynamic Display Switch). On a standard Optimus laptop the internal screen is wired to the integrated GPU and no software setting can change that. On some laptops Advanced Optimus must be enabled in the BIOS first; Razer, for example, has you set Chipset > GPU MODE to NVIDIA Dynamic Display Switch and restart.
Should I use the discrete GPU all the time?
For gaming and plugged in, yes. For battery life on desktop tasks, no — running the discrete GPU constantly drains the battery much faster. Use hybrid or integrated mode for everyday use and switch to discrete for gaming, or let Advanced Optimus decide automatically.