Guides
shadPS4 Best Settings and Crash Fixes: Resolution Patches, Vulkan Errors, Shader Cache (November 2026)
Key points
- Start with the log: right-click the game, Open Path, Open Log Path, open shad_log.txt and read up from the bottom for Critical and Error lines.
- If it quits on launch, check four things first: the Visual C++ 2022 runtime, updated drivers for every GPU, an AVX2 CPU, and program and game folders outside admin-only locations.
- Vulkan 1.3 is required or Required Vulkan extension unavailable means the GPU or driver falls short: update the driver, pick the dedicated GPU on dual-GPU laptops, or replace a GPU that's too old.
- Resolution and frame rate come from per-game patches under right-click, Cheats / Patches. Above 1080p, Digital Foundry recommends an extra 6000MB DRAM allocation or textures won't load.
- The shader cache (Enable Shader Cache) is off by default; with it on, each scene only stutters the first time. If graphics break after a driver or emulator update, delete the game's shader cache.
On this page
When shadPS4 won't start, crashes or shows a black screen, work in this order: read the log, check the basics (runtime, drivers, CPU, GPU), check the game files and modules, and only then look at emulator settings and the game's own compatibility. The log is shad_log.txt, under right-click a game, Open Path, Open Log Path. Only the latest session is kept; read from the bottom up for Critical and Error. For settings, most games are fine on defaults with the shader cache turned on; resolution and frame rate come from per-game patches. This guide reflects shadPS4 v0.21.0 as of November 2026.
Step one: check the basics
| Check | Symptom if it fails | Fix |
|---|---|---|
| Microsoft Visual C++ 2022 runtime (Windows) | Double-clicking the launcher does nothing | Install the x64 runtime |
| Current drivers for every GPU, including integrated | Vulkan errors, crashes | Update from the vendor; the wiki says an outdated driver on an unused GPU can still interfere |
| AVX2 CPU (x86-64-v3) | The program won't open or quits immediately | Only a different CPU fixes it; see requirements |
| Vulkan 1.3 GPU | Vulkan 1.3 is required | Update the driver; otherwise the GPU must be replaced |
| Folder permissions | Odd errors, won't open at all | Keep it out of Program Files, the root of C: and other admin-only places |
| macOS version (Mac) | Won't open | Needs macOS 26 or newer on Apple Silicon |
Recommended settings
The official wiki's advice for Graphics Advanced, vBlank Divider, Logger and Debug settings is the same: don't change them unless you know what they do. These are the ones worth touching:
| Setting (tab) | Recommended | Notes |
|---|---|---|
| Enable Shader Cache (Experimental) | On | Off by default; saves compiled shaders to cut stutter |
| Compress the Shader Cache (Experimental) | Optional | Stores the cache as one zip file instead of many separate files |
| Present Mode (Graphics) | Mailbox (default) or Fifo | Fifo is strict vsync; DF recommended Fifo for Bloodborne |
| Display Mode (Graphics) | Your choice | Windowed / Fullscreen / Borderless; F11 toggles |
| Graphics Device (Graphics) | Dedicated GPU | Choose it manually on dual-GPU PCs |
| Enable FSR / RCAS (Graphics) | Optional | Upscales output and sharpens; doesn't raise internal resolution |
| Readbacks Mode (Experimental) | Disabled (default) | Relaxed / Precise enable GPU memory readbacks some games need; can hurt speed and stability; it's what fixed Bloodborne's vertex explosions |
| Enable PS4 Neo Mode (Experimental) | Off | PS4 Pro emulation; the developers say it's unstable in many games |
| Additional DMem Allocation (Experimental) | 0; raise per game when needed | The developers warn it crashes some games |
| Vblank Frequency (Experimental) | 60 (default) | Changing it can alter game speed or break things |
| Log Sync (Log) | On (default) | Turning it off can help performance a little; keep it on when reporting issues |
Per-game settings: right-click a game, Game-specific Settings. When debugging, right-click, Launch..., Launch with default settings starts it once with defaults so you can rule out your own changes.
Resolution and frame rate: use patches
shadPS4 has no resolution multiplier like Switch emulators do; games render at their original PS4 resolution. For higher resolution or an unlocked frame rate, use that game's patches:
- Right-click the game and open Cheats / Patches.
- Pick a patch repository and click Download Patches.
- Tick what you need (resolution, target FPS, unlocked FPS, LOD, chromatic aberration or motion blur off, depending on the game).
- Start the game.
A reference setup for Bloodborne (Digital Foundry, January 2026)
| Item | Setting |
|---|---|
| Game-specific settings | Present Mode Fifo; asynchronous logging (Log Sync off) |
| Above 1080p | Additional DMem Allocation +6000MB and Vblank Frequency 9999Hz, otherwise textures fail to load and the image distorts |
| Patches | TaskSplit, increased graphics heap sizes, processor-specific workarounds (for example "Intel 12 + SFX"), then resolution, target FPS, unlocked FPS, LOD, chromatic aberration and motion blur off as desired |
| Handheld | On the ROG Xbox Ally X: chromatic aberration off, TaskSplit, Model LOD -2, Uncap FPS (delta time), 720p resolution patch |
| FPS cap | 120 or lower; above 120 running turns into sliding |
| Remaining graphics glitches | Last resort: the Vertex Explosion Fix mod (disables face customization) |
This is specific to Bloodborne. Don't copy the DMem and Vblank values to other games.
Shader cache and stutter
- PS4 shaders are translated and compiled the first time they're used, so the first visit to an area or first use of an effect hitches.
- The shader cache arrived in v0.13.0. Digital Foundry measured 120ms+ spikes in Bloodborne without it. With it on, most hitches happen only once, but since the game has no pre-compilation step, a first playthrough still has some.
- If graphics go wrong after a driver change or emulator update, right-click the game, Delete..., Delete Shader Cache and let it rebuild.
Common errors and fixes
Vulkan
| Exact message (log or dialog) | Meaning | Fix |
|---|---|---|
Vulkan 1.3 is required, but only 1.x is supported by device! | The selected GPU or its driver lacks Vulkan 1.3 | Update the driver; pick the dedicated GPU; a GPU that's too old must be replaced |
Vulkan 1.3 is required, but only 1.x is supported by instance! | The system's Vulkan runtime is too old | Update your GPU driver (it ships the Vulkan runtime) |
Required Vulkan extension unavailable: VK_KHR_push_descriptor (or swapchain, vertex_attribute_divisor, robustness2) | The driver lacks a required extension | Update the driver; if it's still missing, the GPU doesn't support it |
Required Vulkan feature unavailable: robustBufferAccess2 (or robustImageAccess2, nullDescriptor) | The driver lacks a required feature | Same as above |
No physical devices found | No Vulkan-capable GPU was found | Install GPU drivers and try again |
Game files
| Exact message | Meaning | Fix |
|---|---|---|
Failed to open param.sfo | sce_sys/param.sfo (the game info file) exists but can't be read, usually because it's damaged or incomplete | Copy the game folder again and make sure it's complete |
Guest app's main executable ... does not exist / Failed to load game's eboot.bin | The main executable eboot.bin is missing or unreadable | Add the folder that directly contains eboot.bin and sce_sys; don't add the -patch update folder as the game |
No HLE available for libSceXxx module | The game wants a system module that has neither a .sprx file nor a built-in implementation | Put the matching .sprx in sys_modules (per game: sys_modules/<title ID>/) |
Can't Load libSceXxx.sprx switching to HLE | No .sprx found, so the built-in implementation is used | Normal message; only add the module if the game then fails |
A trophy key is required to use the Trophy Viewer. | The trophy viewer needs a trophy key | Enter it under Settings, Manage Cryptographic keys; games play fine without it |
Critical labels in the log
The official wiki groups severe log errors into two kinds. Seeing them usually means something isn't emulated yet, not that your settings are wrong:
| Label | Meaning (per the wiki) |
|---|---|
| AF (Assertion Failed) | The program hit a situation that breaks an internal assumption and can't continue |
| AF:vk_scheduler, AF:vk_graphics_pipeline, AF:vk_rasterizer | Rendering errors, usually GPU vendor-specific |
| AF:structured_control_flow | The game uses shader instructions that aren't implemented yet |
| AF:memory, AF:address_space | Memory emulation errors; the latter are usually platform-specific |
| UC (Unreachable Code):liverpool_to_vk | An error translating PS4 GPU behavior to Vulkan |
| UC:ajm_instance | An audio decoding error, usually an unimplemented codec |
When you see these, check the game's status and issue history on the official compatibility list, try the latest nightly, or switch back to a version that worked in the Version Manager.
Other common problems
| Symptom | Cause and fix |
|---|---|
| Textures missing or distorted with high-resolution patches | The game is running within PS4 memory limits; raise Additional DMem Allocation for that game (DF used 6000MB for Bloodborne) |
| Game runs too fast or too slow | Vblank Frequency was changed, or an FPS unlock patch without delta time is active; revert or switch patches |
| Text shows as boxes or fonts are missing | Some games need PS4 system fonts in the user folder's fonts (font and font2 subfolders) |
| Update not applied | The update folder must be named CUSAxxxxx-patch and sit next to the game folder |
| DLC missing | Separate DLC goes in a folder named after the game inside DLC Path; license-only DLC goes in licenses |
| Controller not responding | Xbox and DualShock controllers work out of the box per the developers; enable "Enable Background Controller Input" under Settings, Input if the window isn't focused; bindings are saved per game, so check that game's mapping |
| Crashes with patches or cheats on | Turn off all patches, cheats and mods and reproduce; the developers don't support issues with them enabled |
| Online play won't connect | Since v0.20.0 online uses shadNet: register an account on the shadNet site and turn on Enable shadNet under Network; the developers say compatibility is still very limited |
| Crashes on Mac | Some are Rosetta 2 translation problems, and v0.20.0 and v0.21.0 fixed a batch; update to the latest release or try a nightly |
Before you report a problem
- Turn off all patches, cheats and mods and try Launch with default settings.
- Make sure you're on the latest stable or latest nightly.
- Keep logging on (Enable Logging) with Log Sync on, reproduce the issue and find
shad_log.txt. - Look up the game on the official compatibility list to see whether someone has reported the same thing. The official Discord also helps.
For platform-specific issues see the Windows guide, the Mac guide and the Steam Deck and Linux guide. Bloodborne specifics are on the Bloodborne page.
FAQ
shadPS4 crashes as soon as I start a game. What should I do?
Read the last lines of shad_log.txt for Critical errors. The usual causes, in order: no Visual C++ 2022 runtime, outdated GPU drivers (update every GPU), a CPU without AVX2, a GPU without Vulkan 1.3, an incomplete game folder, or a game that simply isn't compatible yet. Check the game's status on the official compatibility list and try the latest nightly.
How do I fix 'Vulkan 1.3 is required, but only 1.2 is supported by device'?
The GPU shadPS4 picked, or its driver, only supports Vulkan 1.2. Update the driver from your GPU maker first. On dual-GPU laptops, select the dedicated GPU under Graphics Device in settings. If the driver is already current, that GPU is too old for shadPS4.
Why does shadPS4 stutter every time I enter a new area?
That's shaders compiling for the first time. Turn on Enable Shader Cache on the Experimental tab (it's off by default) so compiled shaders are saved and the same scene won't stutter again. Digital Foundry measured 120ms+ spikes in Bloodborne without the cache when entering new areas or hitting an enemy for the first time.
How do I get 4K or 60fps in shadPS4?
There's no global resolution scale. Right-click the game, Cheats / Patches, pick a patch repository, Download Patches, then tick that game's resolution and frame rate patches. Above 1080p, Digital Foundry recommends raising the extra DRAM allocation to 6000MB in the game-specific settings. Unlocking FPS needs a delta-time patch, or the game runs at the wrong speed.
Textures don't load and the image distorts with a high-resolution patch. Why?
The game is still running within PS4 memory limits. Digital Foundry's fix is to add 6000MB under Additional DMem Allocation in the game-specific settings and set Vblank Frequency to 9999Hz. Changing Vblank has side effects (the developers warn it can change game speed or break things), so only change it for games that need it.
What does 'No HLE available for ... module' in the log mean?
The game asked for a system module, and shadPS4 found neither a .sprx file for it in sys_modules nor its own implementation. The game may fail because of it. Put the matching .sprx in the user folder's sys_modules (or sys_modules/<title ID>/ for one game only) and try again.
I added an update or DLC but nothing changed in the game.
The update folder must be named CUSAxxxxx-patch (or CUSAxxxxx-UPDATE) and sit at the same level as the game folder; the game list then shows the new version. Separate DLC goes in a subfolder named after the game folder inside your DLC Path; license-only DLC goes in the user folder's licenses.
Running in Bloodborne turns into sliding after unlocking the frame rate.
Digital Foundry found that above 120fps, Bloodborne's run turns into slow sliding movement in shadPS4. Cap the frame rate at 120 or lower and it doesn't happen.
Sources
- shadPS4 compatibility list
- shadPS4 blog: v0.20.0 (shadNet online play, 2026-10-13)
- shadNet (shadPS4's online service)
- Digital Foundry: Bloodborne PC Emulation Can Now Exceed 4K at 60FPS (2026-01-17)
- Digital Foundry: ROG Xbox Ally X Runs Emulated Bloodborne Faster Than PS4 and PS5 (2026-01-17)
- Wikipedia: shadPS4 (readbacks and Bloodborne's vertex explosions)