Hardware-accelerated GPU scheduling on or off for gaming?
On if you use DLSS Frame Generation, because NVIDIA's own guide says frame generation is unavailable without it. Otherwise it makes no difference you can count on. No one has published an input lag test of HAGS, Microsoft promises no latency gain, and the one big benchmark found no gain in fps either.
Turn hardware-accelerated GPU scheduling on if you use DLSS Frame Generation, because frame generation will not run without it. If you do not, leave it however it is set. No one has published an input lag measurement for it, and the sources that exist point the same way. Microsoft says "users should not notice any significant changes". The largest benchmark found no fps gain in any game it tried.
What hardware-accelerated GPU scheduling is
Several programs can want the graphics card at once: the game, the browser, the desktop. Something has to decide whose work runs next. That job is GPU scheduling.
Before 2020, Windows did it on the main processor. In Microsoft's announcement, Steve Pronovost describes "a high-priority thread running on the CPU that coordinates, prioritizes, and schedules the work". Hardware-accelerated GPU scheduling, or HAGS, moves that job onto the graphics card. Windows can now "offload most of GPU scheduling to a dedicated GPU-based scheduling processor".
It arrived in the Windows 10 May 2020 update. It needs "recent GPUs that have the necessary hardware" and a WDDM 2.7 driver, which is the driver model Windows uses to talk to the card. At launch Microsoft shipped it "off by default", as an opt-in for early adopters.
Why two answers circulate
The "on for lower lag" story comes from Microsoft's own post. It explains that games keep the CPU a frame ahead: the GPU works on frame N while the CPU prepares frame N+1. Then it says "an inherent side effect of buffering between CPU and GPU is that the user experiences increased latency." That frame waiting in line is the render queue, covered in our Reflex and Anti-Lag guide.
Read quickly, that sounds like a promise. It is not one. The same post says the new scheduler cuts the cost of scheduling, but "most applications have been designed to hide scheduling costs through buffering." The queue stays. HAGS does not remove it. The post names no latency gain and no figure. It calls this first phase a way "to set the stage for things to come".
The "off" story comes from benchmarks where HAGS made a slow CPU slower. Those exist, but they are about frame rate, not lag.
What the benchmark found
Gamers Nexus tested six games in July 2020, on a four-core i3-10100 and a ten-core i9-10900K. Their summary: "We didn't see significant framerate improvement nor frametime consistency uplift in any games." They did not test input lag.
| Game | HAGS off | HAGS on | What it means |
|---|---|---|---|
| F1 2019, 1080p | 167 fps average, 79.5 fps 1% low | 163 fps average, 75.4 fps 1% low | Each frame about 0.15 ms longer (5.99 to 6.13 ms) |
| Red Dead Redemption 2, DX12, 1080p Medium | Frame times about 10 to 11 ms | About 18 ms, with higher spikes | About 7 to 8 ms longer per frame. Gamers Nexus calls it a bug |
| GTA V | 93 and 94 fps | Within test variance | |
| Hitman 2, The Division 2 | No difference, or near-identical averages | No change | |
| Total War: Three Kingdoms | Under 1% higher with HAGS on | No meaningful change | |
On the i9-10900K, results were nearly identical in every test, on or off. So the only harm they found was on a slow CPU, and the only gain was too small to separate from noise.
Worked through: two players, two answers
Take a player on Windows 10 with an RTX 40 series card. They open a game, and DLSS Frame Generation is greyed out. Walk the requirements in NVIDIA's Streamline guide for frame generation. Windows has to be version 2004 or newer, build 19041 or higher. Then "Hardware-accelerated GPU Scheduling (HWS) must be enabled". The guide adds: "If any requirement is not met, DLSS-G will be unavailable." 505 Games' support page says HAGS is disabled by default on Windows 10. So the fix is one switch and a restart. Here HAGS goes on, and there is no choice to make.
Now take a second player with an i3-10100 who never uses frame generation. Suppose they play a game like F1 2019, as tested in 2020. Going by Gamers Nexus, HAGS on costs them about 4 fps, or 0.15 ms per frame. That is not a lag figure, since nobody measured lag. In Red Dead Redemption 2 under DX12, the same CPU's frames ran about 7 to 8 ms longer with it on. For that player, off is the safer setting, and a test in their own game settles it.
How to set it
- Open Windows Settings, then System, Display, Graphics. NVIDIA's guide gives the full path as Settings, System, Display, Graphics, Change default graphics settings.
- Switch Hardware-accelerated GPU scheduling on or off.
- Restart the PC. 505 Games says to restart before you relaunch the game.
- If frame generation is still greyed out, update the graphics driver and Windows. 505 Games notes that frame generation "requires newer drivers".
On or off, by situation
| Your situation | Set HAGS to | Why |
|---|---|---|
| You use DLSS Frame Generation | On | NVIDIA lists it as a requirement. Without it, frame generation "will be unavailable" |
| Frame generation is greyed out on Windows 10 | On, then restart | Off by default on Windows 10, per 505 Games |
| No frame generation, no problems | Leave it as it is | Microsoft: no significant change. Gamers Nexus: no fps gain in any game |
| A game stutters or its frame times got worse after you turned it on | Test it off | Gamers Nexus saw RDR2 frame times rise from 10 to 11 ms to about 18 ms on an i3-10100 |
To test, play the same scene with HAGS on and then off, and compare frame times and 1% lows, not average fps. If you care about lag itself, measure it before and after. That is the test nobody has published.
The verdict
- HAGS moves GPU scheduling from the CPU to the graphics card.
- Using DLSS Frame Generation: turn it on. NVIDIA's guide says frame generation is unavailable without it.
- Not using frame generation: it does not matter for latency. No published test measured a change, and Microsoft promises none.
- If a game stutters after you turn it on, test it off and compare frame times.
- For milliseconds that are real, start with the settings checklist.
Where this stops applying
The only large benchmark is from July 2020, on drivers 451.48 and 20.5.1 beta, with six games. Drivers and Windows have changed many times since, and the RDR2 bug may be long fixed. The frame generation rule here is NVIDIA's DLSS Frame Generation. We found no source stating what AMD's or Intel's frame generation needs, so this page makes no claim about them. Nothing here is a latency measurement, because none exists in anything we could find. If one is published, it decides the no-frame-generation case, not this page. Like HPET and USB selective suspend, HAGS is a Windows switch that circulates as a lag fix with no measured lag behind it.
Frequently asked questions
Does hardware-accelerated GPU scheduling reduce input lag?
No published test shows that it does. Microsoft's announcement gives no latency figure and does not say the feature lowers latency. It says "users should not notice any significant changes", because "most applications have been designed to hide scheduling costs through buffering". Gamers Nexus tested fps and frame times, not input lag.
Do I need HAGS for DLSS Frame Generation?
Yes. NVIDIA's Streamline programming guide for DLSS Frame Generation lists it as a requirement, and says that if any requirement is not met, frame generation "will be unavailable". If the option is greyed out in a game, turning on HAGS and restarting is the fix 505 Games gives.
Does HAGS increase fps?
Not in Gamers Nexus's tests. Across six games on an i3-10100 and an i9-10900K, they "didn't see significant framerate improvement nor frametime consistency uplift in any games". In F1 2019 on the i3 it cost 4 fps (167 to 163).
Where is the HAGS setting?
In Windows Settings, under System, Display, Graphics. NVIDIA's guide gives the path as Settings, System, Display, Graphics, Change default graphics settings. Restart the PC after you change it.
Should I turn HAGS off if a game stutters?
It is worth one test. Gamers Nexus found Red Dead Redemption 2 in DX12 ran at about 18 ms frame times with HAGS on and 10 to 11 ms with it off on an i3-10100, and called it a bug. Turn it off, restart, and compare frame times in the same scene. If nothing changes, turn it back on.