Crashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minutePC Slower Than It Used to Be?
A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11Some links on this page are affiliate links: if you buy through them we may earn a commission, at no extra cost to you.
To add a BIOS to RetroArch, find the active folder at Settings → Directory/Directories → System/BIOS, copy the exact firmware file there, and check the selected core’s documentation for its required filename, region, and hash. Not every system or core needs a BIOS, and the folder path can differ by installation.
What a BIOS does in RetroArch
RetroArch uses “BIOS” broadly for firmware, boot ROMs, and other system files that a core may need to emulate hardware. A BIOS is separate from the emulator core, the game ROM or disc image, and save files such as memory-card images. Installing a core does not necessarily install its firmware. Libretro’s BIOS guide explains that requirements vary: some cores require a BIOS, some can use one optionally, and some use high-level emulation (HLE) as a built-in substitute.
Check whether your core needs a BIOS
Identify the exact core you are using before looking for firmware. Two cores that emulate the same console can have different BIOS requirements, filenames, folder arrangements, and options. The Libretro BIOS hub links to core-specific guidance.
- Required: Without the specified file, a core may refuse to start, fail to load some content, or report missing firmware. Examples include some PlayStation CD, Sega CD/Mega CD, PC Engine CD, arcade, and computer emulation setups.
- Optional: A core may run without a real BIOS, but firmware can improve authenticity, compatibility, or behavior. The specific core documentation determines when it is used.
- Not needed: Many cartridge-based systems work without separate BIOS files, depending on the core. Don’t collect a generic BIOS pack before checking what your core actually uses.
Some cores fall back to HLE when a real BIOS is absent. That can make initial setup easier, but HLE is not always equivalent to the original firmware and may have compatibility or accuracy differences.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
Find RetroArch’s active BIOS folder
- Open RetroArch and go to Settings.
- Open Directory or Directories; the label varies by version, interface, and platform build.
- Select System/BIOS and note the path displayed in the file browser or directory list.
That displayed path is the one to use. It may point to a folder named system, but it is not necessarily beside your ROMs or RetroArch executable. Package type, operating system, configuration, and permissions can change the location. Libretro recommends setting the system directory rather than assuming the starting directory is the right place. See the directory configuration guide.
Set a different System/BIOS directory if needed
If the current folder is inconvenient, choose an existing accessible folder—or create a dedicated system folder—and set it in RetroArch:
- Open Settings → Directory/Directories → System/BIOS.
- Browse to the folder you want RetroArch to use and confirm the selection.
- Save the configuration if your build does not save directory changes automatically, then restart RetroArch or reload the core.
If you need to edit the configuration file instead, the relevant variable is system_directory:
Recommended Free Tools
system_directory = "/path/to/retroarch/system"For example, a Windows value might be system_directory = "C:RetroArchsystem"; Linux or macOS might use system_directory = "/home/username/RetroArch/system". Use the path syntax appropriate to your system. In a configuration file, Windows backslashes may need careful handling. Editing the file is best treated as a fallback when the UI cannot reach or retain the desired folder. The Libretro directory guide covers this setting.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Copy the correct BIOS and verify it
Use the core’s own documentation to confirm three things: the expected location, exact filename, and file hash. A BIOS might need a core-specific subfolder or special name. Don’t rename an arbitrary file to bios.bin and expect it to work. Case may matter on some systems; region, revision, file integrity, and whether the file is still inside an archive can matter too.
To check an MD5 hash, run the appropriate command and compare its output with the value documented for your core:
- Windows:
certutil -hashfile "C:pathtobios.bin" MD5 - macOS:
md5 "/path/to/bios.bin" - Linux:
md5sum "/path/to/bios.bin"
A mismatch means the file does not match that documented dump; it may be a different revision, damaged, incorrectly extracted, or otherwise not the expected file. A matching hash checks file identity against the reference, not whether you obtained the file lawfully. Libretro’s BIOS information describes checking location, filename, and hash.
Enable core-specific firmware options
Copying a file into the right directory does not guarantee that a core will use it. Some cores have an option that selects the original boot ROM or firmware. The option name and location vary by core; check its documentation and options menu.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Game Boy and Game Boy Color with Gambatte
Gambatte’s documentation lists gb_bios.bin and gbc_bios.bin as optional. To use them, turn on the core option Use official bootloader. Without that setting, the files can be present yet unused.
Sega systems with Genesis Plus GX
Genesis Plus GX’s documentation distinguishes required regional CD firmware from optional boot ROMs. It also documents core options for certain boot ROMs and lock-on ROMs, so check the relevant option as well as the file location.
Example: PlayStation with PCSX ReARMed
PlayStation firmware is a common source of setup problems, but these names and hashes apply to PCSX ReARMed; they are not universal requirements for every PlayStation core. The values below are examples documented on the PCSX ReARMed core page.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
| Filename | Documented description | MD5 |
|---|---|---|
scph5501.bin |
Version 3.0, North American | 490f666e1afb15b7362b406ed1cea246 |
scph1001.bin |
Version 2.0, North American | 924e392ed05558ffdb115408c263dccf |
scph7001.bin |
Version 4.1, North American | 1e68c231d0896b7eadcad1d7d8e76129 |
scph101.bin |
Version 4.4 | 6e3735ff4c7dc899ee98981385f6f33d0 |
PSXONPSP660.bin |
BIOS extracted from a PSP | c53ca5908936d412331790f4426c6c33 |
- Select or install PCSX ReARMed, then consult its core page to confirm the BIOS name and hash you intend to use.
- Copy the matching file to the active System/BIOS directory.
- Load the PlayStation disc content. For a disc dump with a cue sheet, load the
.cuefile so the track layout and filenames are interpreted correctly. - If the game still fails, check the cue sheet and disc-image filenames, the region, and the log as well as the BIOS.
PCSX ReARMed can fall back to an HLE BIOS, but its documentation warns that compatibility can be reduced; some games may show problems such as memory-card issues or black screens.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Example: Sega CD and Mega CD with Genesis Plus GX
Genesis Plus GX documents these region-specific CD BIOS filenames. Use the file matching the game’s region, and confirm any current core-specific details on its documentation page.
| Filename | Documented use |
|---|---|
bios_CD_E.bin |
Required for European Mega CD games |
bios_CD_U.bin |
Required for North American Sega CD games |
bios_CD_J.bin |
Required for Japanese Mega CD games |
bios_MD.bin |
Optional Mega Drive startup ROM |
bios_E.sms, bios_U.sms, bios_J.sms |
Optional Master System boot ROMs |
bios.gg |
Optional Game Gear BIOS |
Some optional boot ROMs or lock-on ROMs are only used when the corresponding Genesis Plus GX option is enabled. A correctly copied file can therefore remain unused until the option is changed.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Confirm that the BIOS is being used
There is no universal BIOS status screen across RetroArch cores. Use the signals available for the specific core:
- The content passes the missing-firmware error and boots.
- The original hardware boot screen appears, if that core supports displaying it.
- The core’s information or system-information screen recognizes the firmware, if available.
- The RetroArch log no longer reports a missing or invalid BIOS.
- A feature that previously failed—such as CD booting or memory-card access—works as expected.
A game that starts is not conclusive proof that the real BIOS loaded: the core may have used HLE instead.
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Troubleshoot a BIOS that RetroArch does not detect
Work through these checks in order. Libretro’s troubleshooting guide also recommends checking the directory, name, version or region, file integrity, and log.
- Confirm the active directory. Reopen Settings → Directory/Directories → System/BIOS and compare the displayed path with the folder where you copied the file.
- Confirm the selected core. Make sure its documentation is the source of the filename, hash, and any subfolder instructions you followed.
- Check the exact name and extension. Look for capitalization differences, hidden extensions, or a doubled suffix such as
scph5501.bin.bin. - Check region and revision. A correctly named file may still be the wrong firmware for the core or content.
- Compare the MD5. A mismatch points to a different or damaged dump, or an incorrect file.
- Check extraction and folder structure. Extract the BIOS from an archive unless the core explicitly supports that format, and look for a required subfolder.
- Check core options. Enable the documented bootloader or firmware setting where required.
- Reload and retest. Restart RetroArch or reload the core so it rereads the configuration and files.
- Inspect the log. Reproduce the failure and look for missing-file, invalid-firmware, or path messages. Record the RetroArch version, operating system and hardware, core name and version, content name, and relevant log lines. For advanced command-line troubleshooting, Libretro documents
retroarch --verbosein its CLI guide. - Check the content too. A bad cue sheet, missing disc track, damaged game file, or regional mismatch can cause a boot failure even when the BIOS is correct.
If one game works and another does not, don’t assume the firmware is the only difference: content region, additional firmware, core-specific rules, or disc-image structure may differ.
Platform-specific path considerations
- Windows: Follow RetroArch’s System/BIOS directory setting rather than assuming the folder is beside
retroarch.exe. The Windows installation guide covers directory configuration. - Linux and macOS: Configuration files may be stored in different locations depending on the build and setup. Those configuration-file paths are not automatically the BIOS folder; use the directory RetroArch displays. See Libretro’s configuration guide.
- Android: Storage access can be restricted by Android version, permissions, and RetroArch build. Grant the needed permission and select a location RetroArch can access from its own directory setting; do not assume desktop paths or a tutorial’s copied path will work. See Libretro’s Android and file-access notes.
- Linux packages and portable installs: Package managers and portable builds may use different configuration and data locations. The in-app System/BIOS path remains the reliable reference.
Source your own firmware lawfully
RetroArch generally does not supply copyrighted BIOS files. Libretro describes BIOS files as copies of the operating system used by emulated hardware and expects users to provide their own in accordance with applicable law. Do not rely on a third-party “full BIOS pack” as a shortcut: it may contain incorrect, renamed, duplicated, or corrupted files, and its contents may not match your core. See Libretro’s BIOS guide.
Quick wins for a faster PC:
Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
