Q: My emulator says "BIOS not found" or "Incorrect BIOS". A: Ensure the file is named correctly (some emulators are case-sensitive) and placed in the correct folder.
Q: The file size is 0KB or 4MB and won't load. A:
Q: Do I need this for regular DS games?
A: No. Regular Nintendo DS games usually run on the ARM7/ARM9 BIOS from the original DS (biosnds7.rom / biosnds9.rom). The biosdsi9.rom is only required if you want to emulate DSiWare or boot the actual DSi System Menu. biosdsi9.rom
BIOS and firmware are copyrighted by the console manufacturer. Emulators document names and required files, but you should obtain BIOS/firmware by dumping them from hardware you legally own; do not download copyrighted BIOS images from untrusted or illegal sources.
Many laptop and desktop manufacturers use a single updater executable (.exe) that, when launched, extracts several temporary files into a folder (e.g., C:\Windows\Temp or C:\Dell\Drivers). One of those temporary files is often biosdsi9.rom. This is the actual payload—the new firmware image—while the executable simply wraps the flashing logic. Q: My emulator says "BIOS not found" or "Incorrect BIOS"
For example, some Acer Aspire and Lenovo ThinkPad models circa 2015–2018 use a Phoenix-based BIOS core that relies on filenames like biosdsi9.rom as intermediate storage before writing to the flash chip.
There is a possibility this refers to a specific, perhaps obscure, embedded board or a "white-box" OEM motherboard. "DSI" is sometimes used in industrial computing (Data Station Interface). Q: The file size is 0KB or 4MB and won't load
If you are verifying your file to ensure it is not corrupted or fake, check the following hashes.
File Details:
Common Hashes (Standard 64KB Dump):
(Note: If your file is 4MB, the hashes will differ. Emulators usually use the smaller 64KB version which contains the executable code section.)