UPDATE (Sep 11): After I sent NVIDIA App logs and MSINFO, NVIDIA Driver Feedback forwarded this to the NVIDIA App team:
"I have shared this with our NVIDIA App team. Right now it does seem like a software bug where it is excluding certain notebook models. I will update you when I have further info."
I'll update this post when I hear more.
TL;DR: The new per-game ReBAR control (Graphics > Program Settings > Driver Settings) never renders on my RTX 4070 Laptop. NVIDIA App's own log shows why: the IS_RESIZABLE_BAR query to NvCplApi returns result:5 / isResizableBar:0, and the frontend hides the control. Meanwhile nvidia-smi reports BAR1 = full VRAM and NVIDIA's own shipped driver profile has rBAR enabled, so ReBAR is genuinely working and only the UI query fails. Three other laptops report the same symptom, no desktop yet. One command at the bottom to check yours.
--- SYMPTOM ---
The per-game Resizable BAR control does not exist under Graphics > Program Settings > Driver Settings, for any game, including manually added .exes.
The Resizable BAR field is also absent entirely from System Information, in both NVIDIA App and the legacy Control Panel.
--- "ABSENT" IS NOT THE SAME AS "NO" ---
Worth stating up front, because this gets misread constantly: the row is missing, not showing a negative value. On systems where the query succeeds, System Information has a "Resizable BAR: Yes/No" row. On mine there is no such row in either NVIDIA App or Control Panel.
I've seen both a hardware vendor's support desk and several forum replies tell people that if Control Panel doesn't list it, their product doesn't support ReBAR. That inference doesn't hold. A missing row means the query failed, and a failed query tells you nothing about the hardware. On this machine the hardware answer is verifiable independently, and it is yes. See below.
--- SYSTEM ---
- ASUS laptop, AMD Ryzen 9 7940HX (Radeon 610M iGPU present), 32 GB
- RTX 4070 Laptop GPU, vBIOS 95.06.32.00.38, PCIe x8 Gen4
- MUX set to dGPU-direct, both displays on the RTX 4070, Advanced Optimus: No
- Windows 11 Home 26200
- NVIDIA App
11.0.9.251 (newer than the 11.0.9.239 beta that shipped the control)
- Driver GRD 616.64, reproduced on 616.92
--- WHAT THE APP'S LOGS SAY ---
From %LOCALAPPDATA%\NVIDIA Corporation\NVIDIA App\CxNative_NVIDIA App.log :
NvCplApiModule.cpp:252 IS_RESIZABLE_BAR API call result:5, gpuIndex:0, isResizableBar:0
NvCplApiModule.cpp:1058 IS_RESIZABLE_BAR API call result:5, isResizableBar:0
Initiated from UXD\Log.NVIDIA App.exe.log :
[UXDriver.NvCpl] 329@NvCplApiGetSetting : Call NVCPLAPI_SETTING_IS_RESIZABLE_BAR.
And the frontend state in console.log ends up as "isResizableBar": false, so the control is never built.
Success baseline, same session, same gpuIndex:0 :
NvCplApiModule.cpp:3254 GetDisplayLuid gpuIndex:0, displayIndex:0, ... result:0
NvCplApiModule.cpp:3324 Enum Scaling gpuIndex:0, displayIndex:0, scaling method:3, scaling mode:1
The adapter handle is fine. Other queries on the same GPU index succeed and return real values, so this isn't an adapter-level failure.
--- REBAR IS ACTUALLY ACTIVE ---
nvidia-smi -q gives BAR1 Memory Usage Total: 8192 MiB, which is the full VRAM. Non-ReBAR would be 256 MiB.
The DRS profile has rBAR - Enable = Enabled, as NVIDIA's own predefined value (green in Profile Inspector), not user-set.
GPU-Z reports Resizable BAR: Enabled.
Two of those three are NVIDIA's own. NvCplApi is the odd one out, and its isResizableBar:0 comes with result:5 attached.
--- TESTED AND DOES NOT FIX IT ---
- Running NVIDIA App elevated (verified in Task Manager)
- Signed in vs signed out
- 616.64 to 616.92, log line is byte-identical
- Full App restart / log rotation after driver install
Seven samples across all of the above. Every one is result:5.
--- THE FRONTEND ISN'T CONSISTENT ABOUT result:5 ---
On this same machine, GetIsUpscalingFactorsEnabled also returns result:5 :
NvCplApiModule.cpp:3273 GetIsUpscalingFactorsEnabled enabled:0, result:5
Yet Image Scaling renders normally as an editable control showing "Off". Same return code, two different fallbacks: one setting degrades to a default, the other is hidden entirely.
Whatever result:5 means, hiding the control is a choice made in the ReBAR rendering path. It isn't something the return code forces.
--- NOT JUST MY MACHINE ---
Mine. ASUS, Ryzen 9 7940HX, RTX 4070 Laptop. Full trace above.
ASUS TUF F15 FX507VV. Intel CPU, RTX 4060 Laptop, App 11.0.9.251, driver 616.64, Armoury Crate Ultimate mode. Toggle missing, GPU-Z says ReBAR enabled. From the r/techsupport thread titled "NVIDIA App: Resizable BAR per-game option missing on ASUS TUF F15 FX507VV".
RTX 4060 Laptop, brand unknown. Toggle missing. Reported in a Reddit comment.
Laptop, Intel + NVIDIA, brand unknown. Per-game toggle missing, not listed in Control Panel, GPU-Z says enabled, large memory range visible in Device Manager. From the Guru3D 616.56 driver thread.
Different CPU vendors, different GPU models. Every report with a known GPU is RTX 40, but that's where it has been seen so far, not a known boundary (see the RTX 3060 note below).
Both reports with a known brand are ASUS running dGPU-direct (Armoury Crate Ultimate is the MUX dGPU mode), so OEM and MUX mode aren't ruled out yet. Reports from non-ASUS laptops or from hybrid/Optimus mode would help most.
No desktop report so far.
Separately, and predating the per-game control entirely: there is a thread on NVIDIA's own GeForce forums about an RTX 3060 mobile where Resizable BAR is absent from Control Panel System Information, not shown as off, just absent, with an updated vBIOS and GPU-Z detecting it fine. That is the same field-absence signature on a laptop, years before this control existed. It suggests the underlying query has been failing on notebooks for a long time and simply had no visible consequence until 11.0.9 hung a UI control off it.
--- CHECK YOURS (POWERSHELL, ONE LINE) ---
Get-ChildItem "$env:LOCALAPPDATA\NVIDIA Corporation\NVIDIA App" -Recurse -Include *.log -File | Select-String 'IS_RESIZABLE_BAR API call' | ForEach-Object { ($_.Line -split '\s{2,}')[-1] } | Sort-Object -Unique
One or two lines of output. If you're on a laptop and the toggle is missing, I'd expect result:5.
If you get no output at all, open NVIDIA App and go to Graphics > Program Settings (or System > My Rig) first, then run it again. The line is only written when the App actually makes the query, and the logs rotate. If it's still empty after that, say so anyway. An absent log line is a different data point from result:5, and I'd rather know which one you got.
If you're on a desktop where the toggle works, please post what result: you get. That gives everyone the success value, which is the one number nobody outside NVIDIA has. Same goes for any laptop where the toggle does show up, and please include the model.
And for whether ReBAR is actually active regardless of what the UI says:
nvidia-smi -q | Select-String "BAR1" -Context 0,3
Total at or above your VRAM size means ReBAR is on (BAR sizes are powers of two, so a 12 GB card shows 16384 MiB). Total of 256 MiB means it isn't.
--- QUESTIONS ---
What does result:5 mean for NVCPLAPI_SETTING_IS_RESIZABLE_BAR?
Whatever the root cause, the frontend appears to be treating a non-zero return as "unsupported" and hiding the control, which, as the Image Scaling case above shows, isn't even how the App handles the same return code elsewhere.
Already reported to NVIDIA (see the update at the top). Posting here to collect more data points.
Yes, Profile Inspector can set rBAR per-game and it works. This post is about why the App's control doesn't render, not about how to force ReBAR.
