Is there a total external storage limit for a Playstation 3?

I have a PS3 Slim connected to an externally-powered USB hub. Is there a limit as to:

1. How many USB drives can be plugged in, and
2. How much total disk space can the system recognize?*

* As an additional clarification, quick searches online show that the maximum size of an individual external hard drive is 1 TB. Does that mean I can plug in say, 2 hard drives that are 1 TB each and the system will recognize it?

• This has attracted real answers but I gotta ask -- why? Would you want this? Commented Jun 26, 2023 at 13:02
• @RichardRast The answers are very helpful and much appreciated. I'm interested in the limits of gaming hardware so they can be utilized more effectively in other ways.
– plu
Commented Jun 26, 2023 at 16:08

Assuming the information I’ve seen in a couple of places online regarding the 2TB per-device limit and 1TB internal drive limit are accurate, the theoretical limit is 505 TB, achieved by upgrading the internal drive to 1TB and connecting 126 2TB storage devices to each of the two USB ports. This limit is a function of limitations inherent in USB itself, which allows only 127 devices to be connected to a single host controller (and each hub counts as one of those 127 devices).

Actually achieving that requires that:

1. The external USB ports are on independent host controllers and the internal Bluetooth controller is not connected via USB. I’ve not been able to find any conclusive information about this, but it’s statistically unlikely for USB 2.0 ports, as almost all platforms use internal hubs. If that is the case, you’re limited to 126 external devices, or 125 if Bluetooth is connected internally via USB.
2. You can actually find a 126 port USB hub. These simply do not exist, at least not as single devices from a USB perspective. Essentially nobody makes a chip that’s more than a four port hub (7 port hubs involve one of these connected to one of the ports of another, higher port counts use similar daisy-chaining). Factoring in a proper balanced tree, you need 22 hubs on each port, which cuts the number of usable external devices to 105/104 (if the ports are on one controller) or 210/208 (if the ports are on separate controllers).

So if we factor in practical hardware limitations, there’s a functional upper bound of 209 TB (assuming regular four-port hubs externally, one internal hub used for the two external ports, and Bluetooth eating one of the device addresses).

In reality, such a setup is unlikely to work very reliably for a number of reasons though, and it’s entirely likely that the PS3’s USB controllers can’t actually handle that many devices (which would further lower that limit).

• I believe it's possible for one USB device to enumerate multiple "mass storage device" endpoints, which you might see on a combo SD card/memorystick/tfcard/etc reader. Commented Jun 25, 2023 at 6:28
• @Shelvacu I suspect that would count as two devices on the bus, so it wouldn't improve the numbers any. Commented Jun 25, 2023 at 14:26
• @Hearth Actually, it would improve the numbers. Endpoints are something different from device addresses, so as long as the device actually presented multiple endpoints on a given address (15 would be the max possible), this would work. Such devices are not exceptionally common though, which is why I did not mention them in my answer. Commented Jun 25, 2023 at 15:56
• Have you tested it up to 127 devices? Some USB hosts can't actually support 127 devices Commented Jun 26, 2023 at 16:12
• @user253751 Excellent point. I’ve updated the answer to more clearly indicate that what I’m stating here is a probable upper bound on how much storage can be used. Commented Jun 26, 2023 at 17:02

From my own testing, my PS3 successfully recognized and was able to run operations from the following sticks connected at the same time to the externally-powered USB hub:

• 1TB USB HDD
• 0.5TB USB HDD
• 32 GB USB stick x2

So the result suggests that there is no limit to the amount of total memory that gets recognized by the PS3, with up to 127 USB storage devices connectable based on the limitations of the USB standard.

It is possible that there is an upper limit of 1.5 TB of readable external storage (source), but it is unclear if that's for just one device, or the total of all connected devices.

I don't believe there's a limit on total number of drives connected by USB

Can the PS3 read any other filesystem than FAT32 for external drives?

According to this, the PS3 supports FAT32 file systems for external drives.

https://en.wikipedia.org/wiki/File_Allocation_Table

FAT32 file systems have either a 2TB limit or 16TB depending on the sector size of the filesystem. However in either case FAT32 cannot hold files larger than 4GB