Memory cards
Memory cards & third-party cards
The PlayStation 2 stores saves — and, once softmodded, your homebrew launcher — on memory cards. Genuine Sony 8MB cards are the gold standard, especially for FreeMcBoot, which installs its boot files onto the card.
Third-party and clone cards exist in larger advertised capacities, but quality varies widely. Some clones are unreliable, report false capacities, or fail to hold a FreeMcBoot install correctly, leading to corrupted saves or a launcher that won't boot. For anything involving FMCB, a genuine Sony card is strongly recommended.
Tip
If you buy a pre-loaded FreeMcBoot card, prefer a seller who uses genuine Sony cards. Keep a second card for plain game saves so your homebrew card stays clean.
The MX4SIO adapter also uses the memory-card slot, but for a different purpose: it reads a microSD card so Open PS2 Loader can load games from it at high speed. That's covered in the Open PS2 Loader section.