Bandwidth Limitations of using USB interface & storage devices?

Last week I needed to get an external drive to relocate a bunch of files between several PCs. I was shocked by how cheap they’d gotten. Picked up 2TB for$39US. Well, that got me thinking.

Like many folks I suspect, my Instrument Libraries are spread across several SDDs - each one larger than the previous one. Strikes me that consolidating them all onto one USB drive would both simplify things and also make it easier to migrate to a new PC when the time comes.

My current PC is long in the tooth but still working fine, but when it does go I’ll loose my Firewire interface and its connection to my RME Fireface400. Based on this Topic, I’ll likely get an RME DIgiface USB and daisychain the Fireface off of it.

I’m wondering at what point would I start seeing the USB’s limitations. Would be nice to have the Project disk portable too, and then there is…

Currently all my music related USB connections just talk MIDI, so not pushing any limits there. But for future planning I’m trying to understand the balance between the convenience of lots of USB devices and bandwidth limitations.

Far from an expert here, but I’ll tell you what I have plugged in my own PC.

  1. Wired mouse
  2. Logitech dongle for wireless keyboard.
  3. Printer
  4. Touch screen
  5. External SSD, 2TB
  6. Digiface USB
  7. MK3 Oxygen 61
  8. E-licencer
  • After a port died recently, I popped in another 2 USB3.0 ports and 4 USB2.0 ports with a breakout from the motherboard, so no USB hubs are used.

  • I have 4 different SSDs plugged in, and all my BFD sounds are on one of them, other instruments and sounds on the C drive along with Cubase.

  • I regularly use BFD 3 with HSO, at least 10 instances of it. The writing is usually dense with many articulations switching and doing their thing. On 24/96, I get about 3.something/3.something ms latency (I can get back to you with the exact number if you want) Under these circumstances, I can’t say I have seen my disk indicator moving above… 5? 10%?

Things are different on my laptop (a Dell E6420 M2520, recently popped in 16 GB of memory)

  • I plug in my Digiface, e-licenser and external SSD. (I use it to move projects around too.)
  • I must take care to disable wireless, or ASIO performance gets a hit.
  • I can still solidly track 4 microphones (haven’t tried more yet) at 24/96 without a hitch.

You see I have not mentioned the disk performance meter here either, because it doesn’t move by much.

So, for me, I think the 5Gb/s bandwith even for a single port is an order of magnitude higher than what I can realistically throw at it. Now that I’m thinking about it, maybe I should test an “N-player orchestra with N-1 drummers” project to see where the disk streaming starts to crap out.

But that price wasn’t SSD though?

The issue of sending additional reams of data over USB probably depends on how much sharing of bandwidth is happening between the USB ports in question.

And that probably depends on the motherboard design - e.g. how are the USB ports assigned to CPU lanes. Bottlenecks may incur when several USB ports share the same motherboard to CPU lanes. e.g. a single lane of PCIe 3.0 maxes out at 8 Gb/s, so two USB 3.0 ports at 5Gb/s each can end up throttled if connected to the same lane.

Use SD3 which loads samples into ram. Kits can be huge like 8gig or even more. I use a m.2 drive for these samples as wait time is down to a couple of seconds. It can’t do that from a usb drive.

Sure is, it’s about the size of a small candy bar. One clue this might be a new world is the price varied by color. I got a blue one, but red ran $10 more I think.

The size seems about right - I’m just stunned at the price. I’ve never seen anything anywhere near that for 2 TB. – I can only hope you didn’t get scammed with a smaller drive faking to be a much large one.

Yeah the price knocked me over too. I’m sure the quality ain’t great & this was the cheapest I saw - all I needed for the task. But you don’t need to go too far up the price curve to find name brands. Windows thinks it’s 2TB.

The video linked in my prior post explains how Windows can be faked into believing a different capacity than the drive actually has. It’s quite fascinating. The explanation starts around 9:12

While the video deals with an SD card scam, I’m guessing a very similar approach would work with a fake SSD.

Also worth noting is that the Amazon product page has the following image:

  • It calls it an HDD, which is what you call a regular hard disk. And that form factor can’t be an HDD, since it’s too skinny to hold even a 2.5" HDD (the kind you find in laptops).
  • The advertised throughput of 100MB/s is only about 20% of regular USB 3.1 Gen 1 throughput approx. 500MB/s
    – side note: 100MB/s is about the throughput of an SD card rated UHS-I speed
  • There are zero reviews (as of now).
  • EDIT to add: “Sold By” name:

More videos about this scam being done with USB drives: and

And this fake SSD story with a picture of the inside of the fake SSD drive: Fake Chinese 500 GB external drive is one clever paperweight (literally) - Neowin

I’m starting to plan a new build but I’m having trouble find a mobo that has decent internal storage ability. I’ve been looking at the Asus X-299 Deluxe due to it’s native TB3 and 3 SSD slots but it only has 1 internal sata port…Gonna go 1TB ssd system drive, 2TB ssd audio drive, and a third ssd for my orchestral libraries but I need some satas for other libraries, manuals, resources, sound libraries, etc. Anything out there that fits the bill??


I should imagine so. My ASUS Rog Strix z390 E gaming has 6 internal sata ports

mkok, looks like a great board but no thunderbolt 3 :frowning:


Do you have a link to a specifications page of the motherboard you’re talking about? – I’ve been unable to find any ASUS motherboards with 3 m.2 SSD slots

Actually it’s an Asus Prime X-299 Deluxe…this is optional- ASUS Hyper M.2 x16 Card V2 is a separate purchase.


But it seems to have 8 x SATA 6Gb/s ports – so not just 1?

Those are external, only 1 internal sata port…I like to keep my harddrives in the case :slight_smile:

What makes you think they are external?

Just been to the link and it says the ports are internal?

Yup, only 1 internal sata port, the other sata ports are on an exterior post. Check out the images :slight_smile:



I believe you are misinterpreting the images.

The external (USB, ethernet, etc.) ports (ending up at the outside back of the case) are on the opposite edge of the SATA ports (ending up on the front inside of the case) . So while the SATA ports are facing sideways at the edge of the motherboard, they are still internal:

Or if you prefer a schematic (from the ASUS installation manual):

The left ends up on the back outside of the case, and the right ends up in the front, but inside the case.

And to confirm what @mkok mentioned: The ASUS specifications page confirms them as internal ports: