FunTuna, Fortuna, and OpenTuna Versions for Late PS2 Slims

If your PlayStation 2 is a late Slim, standard FreeMCBoot will not boot automatically at power-on, and no FMCB version number fixes that. Late SCPH-90000 consoles from the third quarter of 2008 onward, with datecode 8C and later and boot ROM 2.30 and newer, plus the PS2 TV, fall outside FMCB’s auto-boot support. For those consoles, the route is different: a manual trigger through the console’s own browser menu, using the Fortuna exploit family.

The three names in this guide — Fortuna, FunTuna, and OpenTuna — describe that family, not three unrelated hacks. Understanding which name means what stops the most common late-Slim mistake: installing standard FMCB files, powering on, and assuming the install failed when nothing happens.

First, check whether this guide applies to you

Before touching any Fortuna-family package, confirm your console actually needs it:

• Find your model and datecode. These are on the console label. Late SCPH-90000 models are the main group here.
• Check the ROM version. Datecode 8C was a transition period, so datecode alone does not settle it. The ROM version is the deciding check, and it can be read with homebrew tools once you have a way to run them, or from documentation for your exact model revision.
• Remember the PS2 TV. It is also outside FMCB auto-boot support, even though it is not a standard Slim.

If your console is an earlier Fat or Slim, or a late Slim with an older boot ROM that still supports FMCB auto-boot, you do not need this guide. Use the standard FMCB route from the Download page instead. Installing a Fortuna-family package on a console that auto-boots FMCB fine only adds complexity.

Fortuna: the original exploit

Fortuna was released on 12 February 2019 by krat0s. It is a homebrew launcher for most PlayStation 2 models, covering consoles from ROM version 1.90 (SCPH-18000) up to the very last models, including the PS2 TV. It was not ported to the SCPH-10000 and SCPH-15000 models, so those early consoles are outside its range.

The trigger is what makes Fortuna different from FMCB, and it must be understood before installing anything. Fortuna does not boot automatically when you switch the console on. Instead, you go into the console’s browser menu, select the memory card icon, and back out to the main menu. That sequence triggers the launcher. Every time you want to reach homebrew, you repeat that manual step. If you expect Fortuna to behave like FMCB’s automatic boot, you will think it is broken on the first try. It is not broken; manual triggering is the design.

Fortuna also needs different files depending on the console version. There is no single universal file set that covers every model, which is why guides for Fortuna-family packages stress matching the package to your console. A file set for one revision applied to another is a common cause of a trigger that simply does nothing.

FunTuna and OpenTuna: what the other names mean

FunTuna is the name used for a Fortuna-based package aimed at late Slim consoles, particularly the SCPH-9000x models that cannot auto-boot FMCB. Think of it as a prepared package built around the Fortuna trigger, rather than a separate exploit with its own trigger mechanism. The practical details — which files it contains and how they are arranged — vary between packages, so this guide does not describe a single FunTuna file list as if it were universal. Check the contents and instructions of the specific package you are using, and match it to your console revision before installing.

OpenTuna is the open-source version of Fortuna. It supports almost all PlayStation 2 models from the SCPH-18000 onward to the very last, again excluding the 10000 and 15000 models that Fortuna was not ported to. The practical difference for most users is provenance and maintenance: OpenTuna is the open-source implementation of the same trigger idea, while FunTuna is a packaged route built for late Slims. Neither changes the core facts: manual trigger, not auto-boot, and files matched to the console version.

Choosing between them, honestly

For a late SCPH-9000x Slim, the question is rarely “Fortuna or FunTuna” in the abstract. It is “which prepared package matches my console revision, and are its instructions complete?” Use this checklist:

1. Confirm the console needs this route. Model, datecode, and ROM version, in that order.
2. Pick a package whose instructions name your revision. Vague “works on all Slims” claims are a warning sign, because file sets differ by console version.
3. Expect the manual trigger. Practice the browser sequence — select the card, back out — and do not reinstall repeatedly because auto-boot did not happen.
4. Keep FMCB expectations separate. Once the Fortuna-family launcher runs, you can launch homebrew applications, including a loader, but that does not turn the setup into an auto-booting FMCB install.
5. Note what you installed. Write down the package name, its source, and the console revision it was matched to. Late-Slim setups are the ones most often broken by a later “helpful” reinstall with the wrong files.

Also keep the usual FMCB limits in mind. A Fortuna-family launcher does not by itself add import or copied-disc support, which is a hardware limitation, and it does not turn your console into a different machine. It gives you a reliable way to launch homebrew on a console that cannot auto-boot FMCB. That is a valuable thing on its own, and overselling it only creates disappointment.

For the standard route on supported consoles, see FreeMCBoot Version History: From 1.8 to 1.966 and FreeMCBoot Installer Versions and the Noobie Package Explained.

FAQ

Why does nothing happen when I switch on my late Slim? Because Fortuna-family routes do not auto-boot. Go to the browser menu, select the memory card icon, and back out. That manual sequence is the trigger. If you installed standard FMCB files instead, that is a different problem: standard FMCB cannot auto-boot on late SCPH-90000 consoles with ROM 2.30 and newer.

Does FunTuna work on all PS2 Slims? No. FunTuna is aimed at late Slims that cannot auto-boot FMCB, and file sets differ by console version. Match the package to your exact revision, and do not assume a package for one revision works on another.

What is the difference between Fortuna and OpenTuna? Fortuna is the original exploit by krat0s, released on 12 February 2019. OpenTuna is the open-source version of Fortuna. Both use the manual browser trigger and both exclude the 10000 and 15000 models.

Can I use Fortuna on a PS2 TV? Fortuna’s range includes the PS2 TV, which is outside FMCB auto-boot support. As with any Fortuna-family route, expect the manual browser trigger rather than automatic boot.

Should I install FMCB or Fortuna on a late Slim? If your late Slim cannot auto-boot FMCB, the Fortuna route is the answer for that console. Do not keep reinstalling standard FMCB files hoping a different version will auto-boot; the limit is in the console’s boot ROM, not in the FMCB version number.

Open PS2 Loader Versions and exFAT Support Explained

Open PS2 Loader (OPL) is the application most FreeMCBoot users actually spend their time in, and it is also the application most often confused with FreeMCBoot itself. The key point up front: exFAT support is a feature of modern OPL builds, not a feature of the FreeMCBoot core. If a page credits FMCB 1.966 with exFAT support, it has mixed up the bootloader and the loader.

FMCB is the software that boots from your memory card and gives you a menu. OPL is a separate application launched from that menu, and it is OPL that reads games from USB, network, or hard drive storage. Updating FMCB does not update OPL, and an OPL version number tells you nothing about your FMCB version.

What OPL does, in one paragraph

OPL loads games from three kinds of storage: a USB drive attached to the console, a network share over SMB, or an internal hard drive on a Fat PS2. On USB and hard drive setups, OPL expects a folder structure on the storage device, with DVD games in a DVD folder and CD games in a CD folder, and file names kept to plain characters to avoid parsing problems. Those details belong to OPL, not to FMCB, and they are why an OPL guide reads differently from an FMCB install guide: one is about booting, the other is about finding and launching games reliably.

Where exFAT fits, and where it does not

The old file system story is simple. FAT32 is the long-established choice for PS2 USB storage, but a single file on FAT32 cannot exceed 4GB, which is a problem for larger games. exFAT removes that single-file limit, which is why it matters for USB game storage.

The attribution story is where guides go wrong. exFAT support arrived with modern OPL builds. It did not arrive as part of FMCB 1.966, and it is not something the FMCB core provides to every application automatically. An old OPL build will not gain exFAT support because you updated FMCB, and a modern OPL build does not need a particular FMCB version to offer exFAT. Keep the two update cycles separate in your head and in your notes.

This guide deliberately does not name a single OPL version number as “the exFAT version.” OPL has been distributed in many builds over a long period, and naming a version without checking it against the OPL release notes would repeat the exact kind of error this guide is correcting. The practical rule is safer and more useful: if exFAT matters to you, check the release notes of the OPL build you are about to install, confirm exFAT is listed for that build, and test with one game before moving a whole library.

Choosing an OPL build without chasing numbers

OPL users often ask “which version should I download?” as if a single number settles it. A better approach is to choose by requirements:

1. List what you need first. USB or network or hard drive? exFAT or FAT32? A modern build or a build known to work with a specific setup?
2. Check the build’s own notes. Confirm the storage modes and file systems it supports, rather than trusting a tutorial’s summary.
3. Update OPL separately from FMCB. After installing FMCB 1.966 from the Download page, add or update OPL as its own step, and note the build you installed.
4. Test with one game. Load a single game end to end before copying a library. A build that lists a feature but fails on your console and storage combination has told you something a version number cannot.
5. Change one thing at a time. If a game fails, do not update OPL, change file systems, and swap drives in the same session.

For the FMCB side of the setup, see FreeMCBoot 1.966: What’s New vs 1.965 and 1.953 and FreeMCBoot Installer Versions and the Noobie Package Explained. For the storage hardware itself, see Best USB Drive, microSD, and MX4SIO Adapter for PS2 and Fat PS2 Hard Drive Kit: Network Adapter, SATA Adapter, and Drive.

Common OPL version mistakes

• “I updated FMCB, so OPL is updated.” No. They are separate programs with separate versions.
• “exFAT is a FMCB feature.” No. It is a modern OPL build feature. Credit it to OPL.
• “The newest build is always best for my setup.” Not necessarily. A build that works with your console, storage, and network setup beats a newer build that does not, and the only way to know is to test.
• “My old guide’s OPL steps must still be right.” Possibly, but file system support, folder handling, and settings change between builds. Match your steps to the build you installed.

FAQ

Do I need FreeMCBoot to use OPL? On a console, yes, in the sense that you need a way to boot homebrew, and FMCB is the usual route covered on this site. OPL itself is still a separate application that you install and update on its own.

Does FMCB 1.966 add exFAT support? No. exFAT support comes from modern OPL builds. Updating FMCB alone does not add it, and an old OPL build does not gain it from a new FMCB install.

Should I use FAT32 or exFAT for USB games? If your OPL build supports exFAT and you have games larger than the FAT32 single-file limit, exFAT is the practical choice. If you are on an older build or an older guide, FAT32 remains the compatible fallback. Check your build’s notes either way.

Why do my games not show up in OPL? The usual causes are folder structure, file naming, a fragmented or incompatible drive, or settings for the storage mode you are using. Work through one cause at a time, and confirm the folder layout your OPL build expects before reformatting anything.

Where do I get OPL? From the OPL project’s own distribution, checked against its release notes for the build you want. This site’s Download page is the starting point for FMCB itself; OPL is a separate download with its own version line.

FreeMCBoot Installer Versions and the Noobie Package Explained

The most common confusion in FreeMCBoot guides is not about consoles. It is about packages. People download one thing, follow a guide written for another, and then wonder why files are missing or extra. The short version: the author’s release package contains only what FreeMCBoot itself needs, the installer is the tool that writes it to a card, and the Noobie package is a community bundle that adds applications on top.

Once you can tell those three apart, most “missing file” problems explain themselves.

Three things with similar names

The author’s release package does not include Open PS2 Loader, uLaunchELF, ESR, or a media player. That is not an omission or a broken download. It is how the package is defined: FMCB is a bootloader, and applications are separate software that you add yourself afterwards. If a guide lists applications as “included” and your download does not have them, the guide is describing a bundle, not the author’s package.

The installer deserves its own paragraph because its version number causes constant mix-ups. Installer source version 0.987 is named alongside FMCB 1.966. That does not make 0.987 a newer or older FMCB version. It is the version of the installer code. When you run the installer on the console, you are using a tool to write FMCB, configure its options, and prepare the card. When you reboot afterwards, what runs is FMCB itself, at version 1.966 if that is what you installed.

What the Noobie package is, and when it helps

The Noobie package is a bundle aimed at first-time installers. Instead of collecting FMCB and each application separately, you get a prepared set in one download, including the applications most guides assume you will want: a loader, a file manager, and the other utilities that make a fresh card immediately useful.

That convenience has real value, but it also has costs that should be stated honestly:

• You inherit someone else’s choices. The bundle’s application versions and configuration are the bundle author’s choices, not necessarily the latest version of each application.
• Troubleshooting gets harder. When something fails, you have to work out whether the problem is FMCB, an application, or the bundle’s configuration, rather than checking one piece at a time.
• You still need an entry point. A bundle does not remove the basic install requirement: you need a way to run the installer on the console in the first place, such as an already-modified console, a cheat disc, FreeDVDBoot, or a PC memory card adapter method. See the Tutorials hub at /tutorials/ for the routes.
• Bundles age. A bundle prepared years ago will contain old application versions. That is fine if you know it and update afterwards, and confusing if you assume everything in it is current.

A sensible middle path is common: install FMCB from the author’s package so you know exactly what the bootloader is, then add the applications you actually need, one at a time, from their own sources. It takes longer on day one and saves time on every troubleshooting day afterwards. If you prefer the bundle route, do it knowingly, note which application versions it contains, and plan to update the loader separately afterwards. See Open PS2 Loader Versions and exFAT Support Explained for why the loader needs its own update cycle.

How to tell which package you have

Use this checklist before following any guide:

1. Look for the installer file. If you have an installer you run on the console, you are working with install material, not a finished card image.
2. Check for applications. If Open PS2 Loader or a file manager is already present in the package, you have a bundle or a prepared card, not the bare author’s package.
3. Match the guide to the package. A guide that says “launch the included loader” assumes a bundle. A guide that says “now add your applications” assumes the author’s package.
4. Note the versions separately. Write down the FMCB version, the installer version, and each application version. When something breaks later, that list is the first thing you will need.
5. Do not mix packages mid-install. Starting with one bundle and following steps from a different bundle’s guide is how cards end up with duplicated or conflicting configuration.

What this means for a fresh install

For most people, the cleanest sequence is: get the author’s 1.966 material from the Download page, run the installer using an entry point that works for your console, confirm FMCB boots from the card, and only then add Open PS2 Loader and a file manager. Keep the FMCB version history in mind as well: see FreeMCBoot Version History: From 1.8 to 1.966 and FreeMCBoot 1.966: What’s New vs 1.965 and 1.953 for why 1.966 is the fresh-install choice.

If you already have a working card that came from a bundle, there is no need to tear it down just to prove a point about purity. Note what it contains, back up your saves and configuration, and update applications individually when you have a reason to. The goal is a card you understand, not a card assembled in the most approved way.

FAQ

Why is Open PS2 Loader missing from my FMCB download? Because the author’s package contains only FMCB itself. OPL is a separate application. Add it yourself, or use a bundle that includes it, knowing that the bundle is not the author’s bare package.

Is the Noobie package the same as the author’s release? No. It is a community bundle built around FMCB, containing FMCB plus additional applications. Treat its contents as the bundle author’s selection, and check application versions separately.

What does installer version 0.987 mean? It is the installer source version named alongside FMCB 1.966. The installer writes FMCB to the card; FMCB 1.966 is what boots from the card afterwards.

Can I install FMCB without any applications? Yes. A bare FMCB install boots to the FMCB menu. Applications are what make that menu useful for loading games or managing files, so most users add at least a loader and a file manager straight afterwards.

Should beginners use the Noobie package or the author’s package? Either can work. The bundle is faster on day one; the author’s package plus individually added applications is easier to troubleshoot later. Choose based on whether you value speed now or clarity later, and write down the versions you installed either way.

FreeMCBoot Version History: From 1.8 to 1.966

FreeMCBoot (FMCB) began in 2008 and reached its latest stable release, version 1.966, on 13 April 2019. If you are installing FMCB today, use 1.966. The earlier versions in this guide matter mainly because old tutorials, old cards, and old forum posts still mention them, and it helps to know whether a number you have seen is current, recent, or long superseded.

FMCB was created by Neme and jimmikaelkael, and the 1.9 series has been maintained by SP193. That continuity is part of why the version line is short and stable: this is a mature bootloader for a console that stopped production years ago, not software with monthly feature releases.

The timeline at a glance

This guide deliberately does not reproduce detailed changelogs for every intermediate version. The checked changelog material for this batch covers 1.966 in full, and the dates above for 1.953 and 1.965. Inventing a feature list for a version you cannot check would be worse than leaving a gap, so the gap is stated plainly: if a site gives you a long, specific changelog for 1.953 or 1.965 without a source, treat it as unverified.

What the timeline does tell you is useful on its own. First, 1.953 circulated for about two years, which is why it appears so often. A card prepared in 2017 or 2018, or a tutorial written then and never updated, will naturally mention 1.953. Second, 1.965 was current for only a few months. That short window explains why fewer guides mention it. Third, nothing newer than 1.966 has replaced it as the stable release. A higher number quoted without a source is a red flag, not an upgrade.

The 1.8 era and why old guides still circulate

Version 1.8 belongs to an earlier period of FMCB, when the installer and the surrounding guides looked different from the 1.9-series material most people meet today. Older guides survive because they were copied, mirrored, and linked for years, and because the basic idea — install a bootloader to a memory card, then boot homebrew from it — has not changed.

That survival creates two traps. The first is following an old guide’s file list literally when the current package has different contents. Always match your steps to the package you actually downloaded, and use the Download page as your starting point rather than a random mirror linked from a decade-old post. The second trap is assuming that because a guide is old, its warnings are outdated. Some are not: the need for an entry point to run the installer, the fact that a card cannot be prepared by copying files on a PC alone, and the compatibility limits for late Slims all still apply. See FreeMCBoot 1.966: What’s New vs 1.965 and 1.953 for what the current version does and does not change.

What stayed the same across versions

Version history is usually read as a story of change. For FMCB, the constants are just as important, because they stop a new version number from being oversold:

• The job never changed. FMCB boots homebrew from a PlayStation 2 memory card. It does not become a game loader, a media centre, or an emulator by changing version.
• No applications were added to the author’s package. Open PS2 Loader, uLaunchELF, and ESR remain separate applications, or parts of community bundles. A version bump does not bundle them in.
• Compatibility limits never disappeared. Late SCPH-90000 consoles from the third quarter of 2008 onward (datecode 8C and later, boot ROM 2.30 and newer) and the PS2 TV still cannot auto-boot FMCB. Check the ROM version, since datecode 8C was a transition period. Those consoles need the Fortuna route, covered in FunTuna, Fortuna, and OpenTuna Versions for Late PS2 Slims.
• FMCB alone never added import or copied-disc support. That is a hardware limitation described in the author’s FAQ, and it applies to every version in this timeline.

Which version should you use?

Follow this checklist:

• Fresh install: 1.966. Do not install an older version first and then “upgrade” unless a guide gives you a specific reason tied to your console.
• Working card on 1.953 or 1.965: Leave it alone if it works. Version age alone is not a fault.
• Rebuilding a broken card: 1.966, because its recovery path through mass:/RESCUE.ELF, forced with START+R1, gives you a way back from a bad configuration.
• Fat PS2 hard drive setup: 1.966, because of its updated HDD modules and recompiled disk-checking tool.
• Card or tutorial mentions 1.8: Treat the material as historical. Use a current guide for the actual install steps, and keep the old guide only for background.

Also keep the installer number separate. The installer source code named alongside 1.966 is version 0.987. That is the tool that writes FMCB to the card, not a separate FMCB release, and it should not be confused with the FMCB version itself. See FreeMCBoot Installer Versions and the Noobie Package Explained for how the installer, the release package, and community bundles fit together.

FAQ

Is FreeMCBoot still being updated? The latest stable release is 1.966 from 13 April 2019. No newer stable release has superseded it in the author’s release history used for this guide.

Why does my card say 1.953 if 1.966 is latest? Because 1.953 circulated for about two years and was used to prepare many cards and guides. A 1.953 card is old, not broken, but a fresh install should use 1.966.

Can I update from 1.953 to 1.966 without losing saves? Back up your saves and configuration first, then treat the update as a reinstall following one current guide. Do not update FMCB, your loader, and your storage setup all in the same session, or you will not know which change caused any new problem.

Does a newer version support more consoles? No. The compatibility limits for late SCPH-90000 consoles and the PS2 TV apply across the versions in this timeline. A version number does not remove a hardware limit.

Where should I get 1.966? Start from the Download page on this site, and check the author’s release notes for the version and date before installing anything from another source.

FreeMCBoot 1.966: What’s New vs 1.965 and 1.953

FreeMCBoot 1.966, released on 13 April 2019, is the latest stable version of FreeMCBoot (FMCB). If you are installing FMCB for the first time, 1.966 is the version to use. If you already have an older version running well, 1.966 is a small maintenance update rather than a reason to rebuild a working card from scratch.

The 1.966 changes are narrower than that: a shutdown option, a renamed menu item, updated storage modules, a clearer recovery path, and a recompiled disk-checking tool. None changes which consoles FMCB supports, and none adds applications to the package.

What changed in 1.966

The author’s changelog for 1.966 lists five items. They are worth reading literally, because each one answers a different practical question.

The recovery change is the most useful of the five for everyday users, and it is also the easiest to misunderstand. Recovery mode does not repair a card by itself. It gives you a way back in: FMCB boots the file at mass:/RESCUE.ELF from a USB drive, so you can fix a bad configuration instead of being locked out of your own setup. The START+R1 combination forces that path, which matters when the normal boot configuration is the thing that is broken. If you ever change FMCB settings and the console no longer reaches a usable menu, this is the escape route to remember before you reformat anything.

The storage module update is about Fat PS2 hard drive setups, where FMCB runs from the drive through the Free Hard Drive Boot (FHDB) route. The 1.966 notes describe the update as reducing wear on 2.5-inch drives. That is a design goal, not a promise about any particular drive, so back up your own saves and your own dumps and keep a second copy of anything you cannot afford to lose.

The renamed menu item also prevents a real mistake. “Reload Configuration” could be read as reloading a settings file, while “Restart System” plainly means the console restarts.

How 1.966 compares with 1.965 and 1.953

The honest limit of this comparison is that the detailed intermediate changelogs for 1.953 and 1.965 are not reproduced here, because this guide only reports changelog entries that have been checked against the author’s notes. What can be said with confidence is the timeline and the endpoint: 1.966 is the latest stable release, 1.965 came immediately before it, and 1.953 is an older release from 2016 that still appears in guides and on pre-made cards because it circulated for years.

That timeline explains a common confusion. A card or tutorial mentioning 1.953 is usually just old, not current, and 1.965 was current for only a few months before 1.966 replaced it. For a fresh install, start with 1.966, and only consider an older version as a troubleshooting step for a specific, documented problem.

Also separate the installer version from the FMCB version. The FMCB Installer source code named alongside 1.966 is version 0.987. The installer writes FMCB to a card; FMCB itself is the software that boots from the card afterwards.

Should you update an existing card to 1.966?

Use this decision checklist:

• Fresh install: Use 1.966. Get it from the Download page and follow a current install guide.
• Working card on 1.965 or 1.953, no problems: Leave it alone. An update is not required to keep playing, and every reinstall is a chance to make a mistake with a working setup.
• You use a Fat PS2 hard drive setup: 1.966 is the more sensible choice, because of the updated HDD modules and the recompiled FSCK tool.
• You have broken your FMCB configuration: The mass:/RESCUE.ELF recovery path in 1.966 is a reason to prefer it when you rebuild.
• You are troubleshooting a specific problem: Change one thing at a time. Updating FMCB, updating your loader, and changing storage at the same time makes it impossible to tell which change fixed or caused the problem.

Updating FMCB is not the same as updating Open PS2 Loader (OPL). FMCB is the bootloader on the memory card; OPL is a separate application that loads games. Updating one does not update the other. See Open PS2 Loader Versions and exFAT Support Explained.

What 1.966 does not change

Version updates invite overclaiming, so here are the boundaries that stay the same in 1.966:

• Compatibility is unchanged. FMCB supports PlayStation 2 consoles except late SCPH-90000 models from the third quarter of 2008 onward (datecode 8C and later, boot ROM 2.30 and newer) and the PS2 TV. Always check the ROM version, because datecode 8C was a transition period and cannot be judged by datecode alone. Late Slims need a different route; see FunTuna, Fortuna, and OpenTuna Versions for Late PS2 Slims.
• No applications are included. The author’s release package contains only the files FMCB itself needs. Open PS2 Loader, uLaunchELF, and ESR are separate applications, or parts of community bundles such as the Noobie package. They do not ship inside the 1.966 package, and a guide that says otherwise is describing a bundle, not the author’s release. See FreeMCBoot Installer Versions and the Noobie Package Explained.
• FMCB alone does not add import or copied-disc support. That is a hardware limitation described in the author’s FAQ, not something a version number removes. FMCB boots homebrew from a memory card; it does not turn the console into a region-free or copy-playing machine by itself.
• exFAT is not a 1.966 feature. exFAT support belongs to modern Open PS2 Loader builds, not to the FMCB core. If a page credits 1.966 with exFAT support, it has mixed up the bootloader and the loader.

FAQ

Is 1.966 still the latest FreeMCBoot version? Yes. 1.966, released on 13 April 2019, remains the latest stable FMCB release in the author’s notes. Check any claim of a newer numbered release against the author’s release history before trusting it.

Do I need 1.966 to use Open PS2 Loader? No. FMCB and OPL are separate. You need a working FMCB install to boot homebrew, and OPL itself, updated separately, to load games.

What is the difference between FMCB 1.966 and installer 0.987? FMCB 1.966 is the boot software. Installer 0.987 is the version of the installer source code named alongside that release. One is what runs from your card every boot; the other is the tool used once to write it there.

I have 1.953 on a card that works. Should I worry? No, not on version grounds alone. 1.953 is older, but a working card is a working card. Update when you have a reason — a fresh install, a hard drive setup, or a broken configuration — not because a number looks old.

What should I do before updating FMCB? Back up your saves and configuration, note where your applications live, and follow one guide end to end. Do not combine an FMCB update with a loader update and a storage change in one session.