How to Update PS2 BIOS for PCSX2 (Step by Step)

You cannot update a PS2 BIOS the way you update an app, because Sony never released BIOS updates you could install. In PCSX2, “updating” means adding or switching to a different BIOS dump. You copy the new BIOS files into PCSX2’s BIOS folder, click Refresh List, and select the new version. It takes about two minutes.

If your real problem is an outdated emulator, you need to update PCSX2 itself instead. This guide covers both, plus the Android steps, the real console question, and what to do when the new BIOS does not show up.

Can you update a PS2 BIOS?

No, not in the normal sense. The PS2 BIOS is fixed firmware that came with the console, and there is no official update file. When people say “update PS2 BIOS,” they usually mean one of three things.

What you want	What it really means	Where to look
A newer or different BIOS	Add another BIOS dump and select it in PCSX2	Steps below
A newer emulator	Update PCSX2, not the BIOS	“How do you update PCSX2 itself?”
A repaired console	Fix or replace a damaged BIOS chip	“Can you update the BIOS on a real PS2?”

When should you change your PS2 BIOS?

Change your BIOS when a game fails to boot, shows odd audio or video, or when you want a different region for your games. Do not change it just because a newer version exists. A higher version number does not always mean better compatibility.

These are the common reasons:

Problem	What to try
“BIOS not found” or “invalid BIOS” message	Add a valid BIOS dump and select it
A game crashes at startup	Try a BIOS from the same region as the game
Wrong language or odd timing	Match the BIOS region to the game
Japanese or PAL games act strangely	Add a Japan or Europe BIOS
Games worked before a PCSX2 update	Check emulator settings and paths first

If a game broke right after you updated PCSX2, the BIOS is rarely the cause. Check the BIOS folder path and your graphics settings before you replace anything.

What do you need before you start?

You need a BIOS dump from a PS2 you own, a computer with PCSX2 installed, and a minute to back up your current BIOS folder. PCSX2 is built to use a BIOS dumped from your own console. The BIOS is Sony’s copyrighted software, so we do not link to downloads. If you do not have one yet, follow our guide to dump your own PS2 BIOS. It uses a USB drive and a free tool called bios drain.

A dump often contains several files, not one. Common extras include files for system settings and memory-card data. Keep them together and do not rename them. File names vary by console model, so do not worry if yours look different from someone else’s.

In an emulator, these functions are reproduced together with the virtual PS2 hardware. This is why a compatible BIOS is an important part of setting up PCSX2, AetherSX2, and other PS2 emulators.

How do you update PS2 BIOS in PCSX2?

Copy the new BIOS files into the PCSX2 BIOS folder, refresh the list, select the new BIOS, and test it with a game.

Back up your current BIOS folder. Copy it somewhere safe. If the new BIOS gives you trouble, you can go straight back.
Extract your new BIOS files. If they are in a ZIP or 7z file, unpack them first. PCSX2 cannot read a zipped BIOS.
Open PCSX2 and go to Settings, then BIOS. The page shows the folder PCSX2 is using.
Click Open BIOS Folder. A file window opens in the right place.
Copy the new files into that folder. Put them directly inside it, not in a subfolder. Keep your old BIOS files there too.
Return to PCSX2 and click the Refresh List. The new BIOS should appear with its region and version.
Select it and test. Choose the new entry, start a game, and watch for the PS2 startup animation or the game’s title screen.

For the first test, turn off Fast Boot. If the full startup animation plays, PCSX2 is running the whole BIOS. After that, you can turn Fast Boot back on for everyday play.

Here are the usual default folders if you want to find them by hand:

Platform	Default BIOS folder
Windows (installed)	Documents\PCSX2\bios
macOS	~/Library/Application Support/PCSX2/bios
Linux	~/.config/PCSX2/bios

The Open BIOS Folder button is the safest way, since it always opens the right place. For a full walkthrough on every platform, see our guide to install PS2 BIOS files.

How do you check which BIOS version PCSX2 is using?

Open Settings, then BIOS. The selected entry shows its region and version, for example “USA v02.00” followed by a date. That label tells you which BIOS PCSX2 will load next time you start a game.

If you added a file but the version looks wrong, you probably selected the old entry. Click the new one and save.

How do you update PCSX2 itself?

Open PCSX2’s Help menu and use its update option, or download the newest build from the official PCSX2 website and install it. Updating the emulator often does more for compatibility than changing the BIOS.

Here is what to know:

PCSX2 2.x has a built-in update check on most desktop builds. Look under the Help menu. The exact option name can change between versions.
Download builds only from the official PCSX2 site. Avoid copies on other sites.
Your BIOS and save files usually stay where they are. They live in PCSX2’s data folder, not inside the program.
A portable install keeps its own bios folder next to the program. If you move to a new portable copy, copy your BIOS files across.

After updating, open Settings, then BIOS, and confirm the folder path is still correct. A new install can point to a different, empty folder, which causes a sudden “BIOS not found” error even though your files are fine.

Which BIOS should you choose?

Choose a BIOS that matches your game region. A USA BIOS for American games, a Japan BIOS for Japanese games, and a Europe BIOS for PAL games. Our guide on which PS2 BIOS to use explains every model in detail.

If you only keep one, a USA BIOS is a common choice because it works with the widest range of games. Models such as SCPH-70012 are often recommended for that reason.

Some tips on choosing:

Newer is not always better. A few older games can behave better with an earlier version.
PCSX2 does not lock regions, so a mismatch will usually still boot. It can still cause the wrong menu language, timing, or startup problems.
You can keep several BIOS files in the same folder and switch whenever you like.

How do you update the PS2 BIOS on Android?

Move the BIOS files to your phone, extract them, then import them through the emulator’s BIOS settings. The steps are very similar to the desktop version.

Copy the extracted BIOS files to your phone.
Open your emulator and go to its settings, then BIOS.
Tap Import BIOS and choose your files.
Select the new version and confirm.

AetherSX2 is no longer updated by its developer. NetherSX2 and other newer apps use a similar BIOS screen. If your app finds nothing, check that it has permission to read your storage. Menu names vary between apps.

Can you update the BIOS on a real PS2?

No. There is no official BIOS update for a PS2 console, and you cannot flash a new version from a disc or memory card. If a console has a damaged BIOS chip, the repair is a hardware job, not an update.

That repair means removing the chip and replacing or reprogramming it with special tools. It is risky and best left to a specialist. If your PS2 will not start and you suspect the chip, read our guide to corrupted BIOS symptoms to learn the signs before you pay for repairs.

Also note that running a dump tool on a modded PS2 is not an update. It only copies the BIOS out so you can use it in an emulator.

How do you go back to your old BIOS?

Open Settings, then BIOS, and select the old entry from the list. Nothing else is needed, because the old files are still in the folder. Save, then start a game to confirm it loads.

If you removed the old files by mistake, copy them back from the backup you made in step one. This is why the backup is worth the extra minute.

What is the quick checklist?

Run through this list each time you change a BIOS:

Back up the current bios folder.
Extract the new files and keep them together.
Copy them directly into the bios folder.
Click Refresh List and select the new entry.
Test with Fast Boot off, then switch it back on.
Keep the old BIOS in case you need it.

Why is PCSX2 not showing my new BIOS?

The most common causes are a zipped file, a wrong folder, or a list that was not refreshed. These fixes solve most cases.

Problem	Likely Cause	Fix
New BIOS missing from the list	Files still zipped	Extract them, then copy the raw files
New BIOS missing from the list	Files in a subfolder	Move them straight into the bios folder
List looks the same	Not refreshed	Click Refresh List
“BIOS not found” after a PCSX2 update	New install uses a different folder	Check the path in Settings, then BIOS
Version number looks wrong	Old entry still selected, or an incomplete dump	Select the new entry or dump again
Startup animation plays, game will not load	Region or version mismatch	Try a BIOS from the game’s region
Game still crashes	Not a BIOS problem	Check the ISO and graphics settings

If nothing helps, delete the new files and copy them in again. Interrupted copies are a surprisingly common cause. If the problem continues, your dump may be damaged, and dumping again fixes it.

Frequently Asked Questions (FAQs)

Update when a new release fixes a problem you have, or every few months. New versions improve compatibility and performance. Your BIOS does not need regular updates.

No. Newer versions work well for most games, but some older titles behave better on earlier ones. Match the region to your game first, then change versions only if you have a problem.

No. Your saves live in separate memory card files, not in the BIOS. Some system settings, such as language or clock, may reset because they are stored alongside each BIOS.

Usually yes, because PCSX2 does not enforce region locks. Some games may show the wrong language or run with timing issues, so a matching region is the safer choice.

PCSX2 expects a BIOS dumped from a console you own. Downloaded files come from unknown sources and may be incomplete or the wrong model. Dumping your own is the safest route.

No. Keep both. PCSX2 lists every BIOS in the folder, and keeping several makes it easy to test games and switch back.