GAME · FALLOUT 4 · WINDOWS AND STEAM DECK · UNTESTED BY US
Fallout 4 with DXVK on Windows and Steam Deck
How we checked this
- EXE
- Fallout4.exe · game folder (reported)
- Bitness
- 64-bit → x64
- API
- D3D11
x64/d3d11.dllx64/dxgi.dll- DXVK
- 3.1.1 (untested)
- Built-in profile
- Steam Deck only: dxgi.syncInterval = 1, Steam Deck only: dxgi.maxFrameRate = -60 (unverified)
- Conflicts
- ENB
Windows: install and the ENB problem
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Download DXVK from GitHub
Use the official release page only, and check the hash with the verifier on the download page.Check: You have dxvk-3.1.1.tar.gz.
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Open the x64 folder
Fallout 4 is reported to be a 64-bit game, so you need thex64folder. DLLs of the wrong bitness do nothing and give no error (F05).Check: You see d3d11.dll.
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Copy d3d11.dll, dxgi.dll next to the game's .exe
A Direct3D 11 game needs bothd3d11.dllanddxgi.dll(F40); with onlyd3d11.dllthe game fails to create its device (F06). The game’s program is Fallout4.exe in its install folder.Check: d3d11.dll and dxgi.dll sit beside Fallout4.exe.
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Start the game and check
DXVK writes<exe>_d3d11.lognext to the game on Windows (F13). Turning on the HUD is the other check; see the HUD guide.Check: A log file appears next to the .exe.
To undo it, delete the DLLs you copied (F12): see the uninstall guide. The general steps, with the checklist and warnings, are on the Windows install page.
ENB also uses d3d11.dll and dxgi.dll, the same names as DXVK’s. A folder can hold only one file with a given name, so you must choose one tool or chain them under different names. We tested no chain. See overlay and mod conflicts. Use the Game Checker’s folder mode to see what is already in the folder.
Does it help in downtown Boston?
We do not know: we have no measurement. People with heavy mod lists try DXVK hoping to ease CPU bottlenecks in dense areas, and it can also make things worse. Test with a fixed save before and after, as described on the performance page.
Steam Deck: the 45 FPS profile
Our research notes say DXVK has a Fallout 4 profile that is applied only on Steam Deck, when the environment variable SteamDeck=1 is set (Proton does this on the Deck). It is reported to set a sync interval of 1 and a negative dxgi.maxFrameRate of -60, with a source comment about Fallout 4 defaulting to 45 FPS on the OLED screen and breaking above 60. This profile is not in our extract of 100 profiles, so we have not re-read it. The DXVK 2.4 release notes list “Fallout 4 (Steam Deck OLED)”.
| Option | Value | What the option does (upstream comment, our words) |
|---|---|---|
| dxgi.syncInterval | 1 | Force the D3D10/11/12 Vsync interval: 0 = off, n = on with each image shown n times, negative = respect the game. |
| dxgi.maxFrameRate | -60 | Built-in frame limiter for D3D10/11 games; meant for games with frame-rate-dependent physics. 0 = only limit to refresh rate when the emulated mode differs, n = cap at n FPS, -n = cap only when the game briefly runs far above n, -1 = never limit. |
No rows match.
To override it, a community workaround on r/SteamDeck points DXVK_CONFIG_FILE at your own file in the launch options, or uses DXVK_CONFIG inline: DXVK_CONFIG_FILE=/home/deck/dxvk/fo4.conf %command% (see DXVK in Proton). We did not test it on a Deck. A missing file is not an error: DXVK just uses defaults (F30), so check the log shows the file was read (F15).
Next-gen update and mods
Fallout 4’s 2024 update changed some executables for mod tools such as F4SE. We believe DXVK is unaffected, but did not verify it.
Remove DXVK
Delete both DLLs from the game folder (F12).
What we have not tested
- Any run of the game on Windows or Steam Deck.
- The Deck-only profile: not in our extract, not re-read.
- The DXVK_CONFIG_FILE workaround on a Deck.
- Whether DXVK helps in dense areas with mods.
- F4SE and the 2024 update.
Check your own copy
The Game Checker reads your .exe on your device and tells you its bitness and Direct3D version. Our checker also flags files in the game folder that use the same name as DXVK’s DLLs.
Questions people ask
Does DXVK help Fallout 4?
We do not know: we have no measurement. It is a 64-bit Direct3D 11 game, which DXVK handles.
Which DLLs does Fallout 4 need?
d3d11.dll and dxgi.dll from DXVK's x64 folder, next to Fallout4.exe (F40). Reported values; check with the Game Checker.
Does it work with ENB?
ENB uses the same DLL names, so they collide. We tested no chain.
Why is Fallout 4 capped at 45 FPS on Steam Deck OLED?
DXVK is reported to carry a Deck-only profile for that, per its source comment. We could not verify it.
How do I change the Steam Deck frame rate for Fallout 4?
Community workaround: point DXVK_CONFIG_FILE at your own dxvk.conf in the launch options. We did not test it.
Sources
- DXVK 2.4 release notes (Fallout 4, Steam Deck OLED) · accessed 2026-11-07
- DXVK source: built-in profiles (config.cpp at v3.1.1) · accessed 2026-11-07
- DXVK README at v3.1.1 · accessed 2026-11-07