Issues with my USB 3.1 drive

Hi everyone.

I'm running into an issue with a USB 3.1 drive and was hoping someone could lend a hand. Last month, I ordered one of the supposedly fastest sticks available from Amazon—a SanDisk 256GB model boasting read/write speeds of 420/400 MB/s.

The catch is, whenever I plug it into my USB 3.0 card, I can't actually access it. I hear the standard Windows notification sound when it connects, but nothing shows up in My Computer. In Device Manager, it just shows up under Unknown Devices.


It even pops up in the tray under Safely Remove Hardware, but obviously, there's no drive letter assigned to it.


Interestingly, if I plug it into a spare USB 2.0 port on the front of my case, it works perfectly fine.
I also tried plugging it into the USB 3.0 port on my Android box, and it reads it without any issues.

But through that specific USB 3.0 card on my PC, it’s a total dead end. I'm not sure if the card itself is the culprit, since I have several external HDDs and three other USB 3.0 sticks that work flawlessly with it. Is it possible this drive is just too fast for my ancient rig running Windows 7? 😁

It’ll probably be because a dead Windows 7 system is just too "slow" to even recognize it 😁
Most likely, newer gear just doesn't have drivers for Windows 7 anymore.

ps: USB 2.0 is rated at 480Mbps by standard

wearymason4 said:It’s more likely that an old installation of Windows 7 just finds it too "slow" to actually recognize it 😁
Since newer gear usually doesn't come with drivers specifically for Windows 7 anymore.

ps: By standard, USB 2.0 runs at 480Mbps.

If you plug it into a USB 2.0 port and it works, that’ll basically confirm what I was thinking—that the card just isn't quite playing nice with a flash drive like that, even if Windows is.

Maybe try adding a newer card as an add-on to see if that helps, or just dive into the driver situation. Is this a PCI bus card? Also, have you tried a quick Windows restart with the USB stick already plugged into My Computer?

Alright, I gave that a shot too. Before I rebooted My Computer, I tried uninstalling that USB drive showing up as an Unknown Device in Device Manager.

Still getting the same result. It installs the drivers and then hits me with this error: https://ibb.co/m46kH33

It's still not showing up.

Maybe it really is that PCI-E USB 3.0 card. It might just not be compatible.

Honestly, any USB drive claiming more than 128 GB feels a little sketchy to me, mostly because you often run into those fake MBR setups designed to trick you into thinking the capacity is much higher than it actually is. Even the advertised speeds are usually a total lie; in my experience, they rarely break 50-100 MB/s—and writing speeds are typically even worse—even if they claim to be USB 3.0. If you actually bother to run a real benchmark test, you'll see the truth pretty quickly.

driftingcanyon2 said:Any USB drive claiming to be over 128 GB is sketchy at best. Half the time, they just use a spoofed MBR to fake the capacity. Plus, those advertised speeds are total lies; in my experience, you won't see much more than 50-100 MB/s (and even less on writes), even with USB 3.0. Run an actual benchmark if you don't believe me.

Check this out—my Crucial MX500 256GB is almost maxed out, and the numbers are actually solid:

Charles Smith4 said:Check this out, my Crucial MX500 is almost completely full, but the performance numbers are actually pretty impressive:

I mean, what on earth are you keeping on all those massive USB drives? 🤣 256 GB is wild lol..

By the way, you could try going through the Device Manager and manually selecting the device type (like USB storage device); there's a chance it might actually work.

Sometimes systems just refuse to recognize a USB drive on a 3.0 port while it works perfectly fine on 2.0, or vice versa. Who knows what kind of glitch happens after years of using Windows where it just decides a specific stick belongs to some other device entirely.
I've been dealing with this for years, and I still can't figure out why a USB stick or an external hard drive works in one port but fails in another, or why it starts throwing errors. It’s just one of those macOS mysteries.

The only theory I've come up with is that something was once plugged into that specific port, leaving a trace in the registry, and now any device with a similar ID just confuses the system.

But seriously, don't even bother trying to wrap your head around it. It's impossible.

Exactly. Back when I was using Windows 7, if you swapped a USB port, you’d often have to go through the whole headache of reinstalling drivers just to get a camera or a printer to show up. On Windows 10, though, it just works without any fuss. I totally skipped over 😁.

wearymason4 said:Exactly. Back with Windows 7, if you swapped a USB port, you’d often have to reinstall drivers just to get a camera or printer recognized. With Windows 10, it actually works without the headache ( I skipped Eight and 8.1 😁).

Oh, you lucky bastard...

Imagine a massive 22-inch tablet... but without any touch functionality. That was basically my experience with Eight....
It feels like about 90% of the R&D at Microsoft was actually done by us users. None of their operating systems ever worked right out of the box—you always had to wait for a service pack, maybe even a second one. We struggle, we complain, and then they grandly include our fixes in their "service updates." Think about how many people have survived Windows 10 alone...
True, it runs okay, but every time I see an update notification, I get this twitch: what are they going to break this time? Honestly, besides local network sharing, I bet they'll find a way to screw that up too...

So, I decided to install Windows 10 version 1511 on this slower PC of mine just to mess around with some stuff, and after about an hour, I realized it actually runs just as smoothly as my high-end rig. 😁
I popped open the Task Manager, and man, the number of processes hogging memory is like three times lower than what you see on the latest build... 🤦

Michael Jackson10 said:Oh, you lucky bastard...

Imagine a massive 22-inch tablet... but without any touch support. That’s pretty much how my experience with Eight felt...
It honestly feels like users did 90% of the R&D for Microsoft themselves. Not a single OS version actually worked right out of the box; they only stabilized after a service pack, or even a second one. We struggle and complain, and then they grandiosely slap those fixes into a "service" update. God knows how many versions of Windows 10 have survived this cycle...
Sure, it works fine, but every time I see an update notification, I get a little twitch: what are they going to break this time? Aside from local network sharing, which is almost certainly doomed...

It always happens, every single time there's an update—even a cumulative one. Suddenly, password-protected sharing kicks in, and it's a total pain. You can find workarounds like saving passwords to profiles, but that's not realistic for us. If you've got an office with seven or eight people, someone is bound to forget their password, even if they've logged in with the exact same one thirty times a day.
Then the update hits, and everyone panics in the morning because suddenly nobody can access shared folders anymore.

Charles Smith4 said:Check it out, my Crucial MX500 256GB is nearly maxed out, and the numbers look pretty impressive:

Those "great" numbers are a bit of a devil's bargain; true speed is really just a mix of sequential and random performance, and since your random speeds are hovering around 15 MB/s while sequential hits about 200 MB/s, you're likely looking at that realistic average of 50-100 MB/s I mentioned before. Also, while CrystalDiskMark is fine for an SSD, it tends to give flashier results for USB sticks because with a tiny 1 GB sample size like yours, it fails to catch those sudden speed drops that happen once the cache runs out—some brands, like Transcend, suffer from this and tend to inflate their speed claims. If you want the truth, try copying a file larger than 10 GB from an SSD onto the USB stick and watch the speed graph in the macOS file explorer; you'll see the actual dips, revealing a real-world average that’s usually much lower than what the manufacturers promise.

I'm not entirely sure what kind of memory cells manufacturers are using for these sticks, but I bet it’s a lot like how SSDs work: most of the capacity is just slow TLC NAND, and they just designate a small portion to act as SLC for those quick bursts of data—basically working like a cache. Now, depending on how big that chunk is, tiny datasets fit entirely within it, making benchmarks look lightning-fast. But once that cache fills up? Speeds absolutely crater.
Generally speaking, a higher capacity drive should actually hit speeds closer to what the manufacturer promises. It’s simple math: more capacity means more physical chips, and the controllers can run them in parallel, kind of like an internal RAID setup. More chips available means you can shove more data through at once. That’s why you see such massive speed gaps between the smaller and larger capacities in the same product line.

With SSDs, things get even messier. On top of the part of the cells acting as SLC (the fast stuff), they either include a dedicated amount of DRAM or use a portion of the system RAM for caching (like Samsung or Gigabyte). For everyday tasks, this creates the illusion of a super-fast drive, which pretty much covers what the average user needs anyway.
And let’s be real, the average person isn't doing anything intense: just browsing the web or running a single app that occasionally handles small chunks of data...
They don't even need the high IOPS perks of a premium SSD; that kind of power is really meant for data centers handling huge numbers of users simultaneously.

If you look at real-world stress tests where SSDs are intentionally hammered with massive datasets, the sequential speed tanks after that SLC cache (maybe a few dozen GBs) gets filled up—usually after just 10-20 seconds. It drops drastically, sometimes by as much as three times, because the drive starts writing directly to the TLC. After that, it settles into a relatively steady but much slower pace (dropping from 2,000 down to 500), and then you start seeing performance throttling when the controller overheats and kicks in its thermal protection to slow everything down...
So, those advertised speeds in (totally misleading) benchmarks are barely achievable on a brand-new, empty drive using a tiny sample size. Honestly, there's no point stressing over them too much.

At the end of the day, these tests basically turn into a "who has more" competition. Only power users actually notice the differences, and for most people, the jump from an HDD to an SSD is more than enough of a boost (unless they're using some cheap, low-capacity, bottom-tier SSD).

Richard Lee47 said:It happens every single time an update rolls out—even those cumulative ones. Suddenly, password-protected sharing gets toggled back on, and it’s a total pain. People suggest just putting passwords on individual profiles, but that's a non-starter. If you have an office with seven people, someone is bound to forget their login within a week, even if they've been logging in with the same credentials dozens of times a day.
Then the update hits, and there’s a total meltdown in the morning because we can't access our shared folders anymore.

Honestly, just give us version 5. Sure, let them throw up warnings about authorization requirements or whatever, but if I intentionally set things up a certain way after reading their suggestions, why should they override my choice?

User settings should be final. Let them patch their bugs and fix their messy code, but leave my configurations alone.
Since the last update, I'm spending like 30 seconds clicking through menus and "re-detecting" shared drives just to get things working again. It's exhausting. I don't have the energy or the time to play detective every time they dream up something new. I just revert to my old settings and wait for the next update to break something else.
It really ticks me off how they force anyone running a small home network with a few PCs to act like a full-blown IT admin for a massive corporation...