Internal HDD
SMS can read media straight off the PlayStation 2's internal hard drive — in two completely
different ways. There's the classic APA / PFS scheme (the same format HDD-OSD and the OPL-era tools use),
where SMS lists the drive's PFS partitions and browses whichever one you pick; and there's the modern route, a plain exFAT
drive read through the ATA block driver, which shows up as an ordinary massN: device you can fill
with files from any PC. Both live on the same physical disk, so you pick one per boot.
Two ways to use the HDD
SMS is a media player, not a game loader — so the HDD is just another place to keep your video, music and pictures. The catch is that the internal drive can be formatted in one of two schemes, and SMS reaches each one through a different driver stack:
They are mutually exclusive: both paths want to own the internal ATA bus, so whichever one starts first takes it and the other quietly steps aside. You choose which by picking the matching Autostart toggle — see Choosing one below.
| How it appears | APA / PFS | exFAT via ATA (BDM) |
|---|---|---|
| Format on the disk | Sony's APA partition scheme + PFS filesystem | Plain exFAT partition |
| What SMS browses | Any PFS partition on the drive — you pick one from a list | The whole exFAT volume, any folders |
| Device name in SMS | Internal HDD (APA) | massN: (shared BDM mass namespace) |
| Made with | HDD-OSD / OPL-era APA & PFS tools | Any PC — format exFAT, copy files |
| Enable with | Autostart HDD (the APA/PFS row) | Autostart HDD BDM |
APA / PFS — the PS2's native HDD format
The APA partition scheme and PFS filesystem are the PS2's own native HDD formats — the same ones used by Sony's HDD-OSD (the "PlayStation BB Navigator" era) and by the classic homebrew HDD tools. On this kind of drive, SMS lists the PFS partitions it finds on the APA table as a folder-like list. Pick one with Cross to mount it and browse the media inside; SMS remembers the partition you last used and re-enters it automatically on the next boot. There is no required partition name.
SMS_Media. That has not been necessary for a long time
and this build does not look for it — SMS shows you every PFS partition on the drive and mounts the one you choose.
Any partition made with a standard APA/PFS tool works, whatever it is called. If you already have an
SMS_Media partition it will simply appear in the list like any other.Preparing an APA drive
SMS doesn't format drives or create partitions itself — you do that ahead of time with the usual PS2 HDD tools (HDD-OSD, or a homebrew APA/PFS partition manager such as uLaunchELF). The short version:
Format the drive as APA
Initialise the internal drive with the standard PS2 APA scheme, the same way you would for any HDD-OSD / OPL-era setup. This is a one-time step done from a HDD tool, not from SMS.
Create a PFS media partition
Make a PFS partition to hold your media — call it whatever you like. Copy your video, audio and picture files into it (folders inside are fine — SMS browses the raw tree).
Enable the APA path in SMS
Turn on Autostart HDD APA in the settings (or use Start HDD APA now — see Enabling & tips). SMS starts the HDD driver stack and lists the drive's PFS partitions.
Browse and play
Pick the internal-HDD icon in the device menu and press Down into the list. Choose your partition with Cross to mount it, then open any file with Cross as usual — SMS remembers the partition and re-enters it on the next boot. It behaves exactly like every other SMS source — the raw filesystem, no mandatory folder layout.
exFAT via ATA
The modern alternative skips APA entirely. Format the internal drive as plain exFAT on your PC, drop your
media anywhere on it, and let SMS read the drive through its ATA block driver. Because that driver plugs into
the same Block Device Manager (BDM) that handles USB, MX4SIO and i.LINK, the internal drive simply appears as
another massN: device in SMS — no PS2-specific formatting, no partition juggling.
massN: namespacemassN: pool (N =
0, 1, 2…). The number is assigned as devices come up, so a drive is mass0: if it mounts first,
mass1: if a USB stick got there ahead of it, and so on. You browse it by picking its device icon in the
top row, not by memorising the number.Preparing an exFAT drive
Format exFAT on your PC
Connect the drive to a computer (or format it in-bay with a PC-side tool) and format it as exFAT. Leave the allocation-unit / cluster size at the default for the drive's capacity rather than choosing a custom value.
Copy your media
Drag your video, audio and picture files onto the drive — into any folders you like. SMS browses the raw
filesystem, so there is no required folder tree (no OPL-style DVD//CD/ layout).
Fit the drive and enable the BDM path
Install the drive in the console's HDD bay, then turn on Autostart HDD BDM in SMS (or Start HDD BDM
now). SMS brings up the ATA driver and the exFAT volume mounts as massN:.
Browse and play
Select the internal-HDD icon in the device menu and open files just like any other massN: device.
Choosing one — they're mutually exclusive
Here's the important constraint: the APA/PFS path and the exFAT/ATA path both own the internal ATA bus, so only one can be active at a time. SMS enforces this with a simple "first come, first served" rule — whichever backend starts first claims the bus, and the other declines to start for that session.
Practically, that means you decide up front which scheme your drive is formatted for and enable the matching autostart:
| Your drive is… | Turn on | Leave off |
|---|---|---|
| APA-formatted (any PFS partition) | Autostart HDD APA | Autostart HDD BDM |
| exFAT-formatted (a plain drive) | Autostart HDD BDM | Autostart HDD APA |
Autostart HDD BDM is the ATA/exFAT path — "BDM" because the exFAT drive is read through the same Block Device Manager as your other mass devices. Autostart HDD APA is the classic native-partition path.
Can the HDD run alongside USB, MX4SIO, MMCE and SMB?
Yes — the internal-HDD bus contention is only between the two HDD schemes. Whichever HDD path you choose can
run happily at the same time as USB, i.LINK and SMB. Note two other exclusions elsewhere in SMS: MX4SIO and
MMCE share the memory-card (SIO2) bus, so only one of those two runs at once; and the exFAT/ATA HDD is a
massN: device like USB and MX4SIO, so they simply each take their own slot in that shared namespace.
Enabling & tips
On a clean install nothing auto-starts — you turn on exactly what you need. The relevant controls live in the settings menu:
- Autostart HDD APA — brings up the classic APA/PFS path at boot and lists the drive's PFS partitions.
- Autostart HDD BDM — brings up the exFAT drive over ATA at boot as a
massN:device. - Start HDD … now — when a device isn't already running, SMS also offers an on-demand start item, so you can bring the HDD up without a reboot. Handy for testing which scheme your drive actually mounts.
Practical tips
- Match the toggle to the format. An exFAT drive will not mount under Autostart HDD APA, and an APA/PFS partition won't appear under Autostart HDD BDM. If a drive doesn't show up, you almost certainly enabled the wrong path for how it's formatted.
- Big drive? Use exFAT. APA tops out around 2 TB; exFAT lets you use larger drives and skip PS2-side tooling entirely — just format on a PC and copy files.
- Big library already on APA? Keep it. If your drive is already APA-formatted, the APA path reads your existing PFS partitions directly with no conversion — whatever they are named.
- The drive is optional hardware. Everything above assumes a Network Adapter and an internal drive are fitted. Without them, SMS is perfectly happy on USB, MX4SIO, MMCE or a network share.