Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Transcend Offers JetDrive Lite 330 Expansion Cards Up to 512GB for 14-inch and 16-inch MacBook Pro

usernames need to be uniq said:
Can you point to the benchmarks for the port speed? My understanding is that it is a UHS-II slot and there are write speeds getting close to 300MB/s for the best cards that were independently tested.
Click to expand...

I didn't save the link, but I believe this was the review I got that number from. They were testing with an Angelbird AV Pro V60 UHS-II card. Now that I look at it the test they were doing was a "JPEG copy test," so the ~121MB/s they got may well be the read-write roundtrip speed, which would mean the actual read/write speed was roughly double that.

I don't own any UHS-II or III cards, but I did try a 128GB SanDisk Extreme Pro 128GB UHS-I card in mine. Blackmagic Disk Speed Test showed 66.5MB/s write and 89.5MB/s read. That's very close to what I got timing a large Finder copy, so matches real-world performance, and suggests to me that Transcend is just being honest about the speed of these UHS-I cards.

All of which is a long way to say that, now that I'm actually thinking about it, my statement was half-wrong; I wasn't taking into account the interface.

Since the JetDrive Lite 330 is a UHS-I card, it's much cheaper but its speed is limited by that interface. As far as I can tell, the (off-brand) flush-fit 3rd party micro-SD adapters you can buy right now are also only UHS-I, so wouldn't fare any better no matter what card you put in them.

Name-brand UHS-II cards with high write speeds usually cost five times more than UHS-I cards (Transcend's own UHS-II cards are on the order of $1/GB), so the price probably would be 5x higher for the same capacity if these could max out the slot.

That said, given the cost of the laptops we're talking about here, it's a bit of a disappointment that they don't have an "ultra" version, for those who can afford it and want to add reasonably fast storage rather than just cheap storage.
 
Makosuke said:
I didn't save the link, but I believe this was the review I got that number from. They were testing with an Angelbird AV Pro V60 UHS-II card. Now that I look at it the test they were doing was a "JPEG copy test," so the ~121MB/s they got may well be the read-write roundtrip speed, which would mean the actual read/write speed was roughly double that.

I don't own any UHS-II or III cards, but I did try a 128GB SanDisk Extreme Pro 128GB UHS-I card in mine. Blackmagic Disk Speed Test showed 66.5MB/s write and 89.5MB/s read. That's very close to what I got timing a large Finder copy, so matches real-world performance, and suggests to me that Transcend is just being honest about the speed of these UHS-I cards.

All of which is a long way to say that, now that I'm actually thinking about it, my statement was half-wrong; I wasn't taking into account the interface.

Since the JetDrive Lite 330 is a UHS-I card, it's much cheaper but its speed is limited by that interface. As far as I can tell, the (off-brand) flush-fit 3rd party micro-SD adapters you can buy right now are also only UHS-I, so wouldn't fare any better no matter what card you put in them.

Name-brand UHS-II cards with high write speeds usually cost five times more than UHS-I cards (Transcend's own UHS-II cards are on the order of $1/GB), so the price probably would be 5x higher for the same capacity if these could max out the slot.

That said, given the cost of the laptops we're talking about here, it's a bit of a disappointment that they don't have an "ultra" version, for those who can afford it and want to add reasonably fast storage rather than just cheap storage.
Click to expand...
I use UHS-II cards for my Canon R5 camera so it is a perfect match for my new 16" MBP :)

Different websites have tested the fastest SD cards and there are at least 10 that are faster than 250MB/s write speed and mine is a Sandisk 128GB @248MB/s

The link below confirms that Apple says it will cope with 250MB/s
https://www.macrumors.com/2021/10/21/2021-macbook-pro-sd-card-reader-speed/

As UHS-II cards/slots have a second row of pins, it may not be possible to fit in a micro-sd in an almost flush package ie it needs a custom device for the purpose.

UHS-III cards will never hit the market as SD Express will be the next step. That said, CFe Type B cards are slightly bigger but much faster and are shipping in bulk with capacities up to 1TB from multiple OEMs. The problem with SD-Express is that they aren't backward compatible with UHS-II ie put a SDe card in a UHS-II slot and the speed goes back down to UHS-I speeds :-(

I ordered a 1TB MBP but would have preferred a 2TB SSD but the lead-times were too long for me to wait.
 
usernames need to be uniq said:
As UHS-II cards/slots have a second row of pins, it may not be possible to fit in a micro-sd in an almost flush package ie it needs a custom device for the purpose.
Click to expand...
I don't know how it could not be possible to have a more-or-less-flush UHS-II card for these computers. Logic being, all the points of contact necessary to support UHS-II card reads exist inside the MBP, so there's no way that you couldn't make a flush-fit card with pads that mate with those contacts.

Since a microSD card can fit (sideways) in a flush-fit adapter, it's also got to be at least hypothetically possible to reroute the pads on it to the contacts on a flush-fit adapter.

I've never seen an adapter in person, so it's possible there's something in them that I'm not accounting for (or some issue like crosstalk at higher speeds), but it seems like physically there's no reason it wouldn't work.
 
Makosuke said:
I don't know how it could not be possible to have a more-or-less-flush UHS-II card for these computers. Logic being, all the points of contact necessary to support UHS-II card reads exist inside the MBP, so there's no way that you couldn't make a flush-fit card with pads that mate with those contacts.

Since a microSD card can fit (sideways) in a flush-fit adapter, it's also got to be at least hypothetically possible to reroute the pads on it to the contacts on a flush-fit adapter.

I've never seen an adapter in person, so it's possible there's something in them that I'm not accounting for (or some issue like crosstalk at higher speeds), but it seems like physically there's no reason it wouldn't work.
Click to expand...
Definitely no physical reason but the micro SD memory would need to be above the second row of contacts whereas most adapters now are set way back. I guess I am saying that it couldn't be just a new package with a build-in micro SD but a new card physically and electrically.
I am not sure why but micro SD cards are substantially slower than SD cards which also could be the reason for the slow transcend device.
 
usernames need to be uniq said:
I am not sure why but micro SD cards are substantially slower than SD cards which also could be the reason for the slow transcend device.
Click to expand...
This picture of an SD card's guts (an older card, but newer ones look similar inside) gives a pretty good idea of why they're faster:

SD-extreMEmory_2GB_alt_innen.jpg


A full-sized SD card may be small, but it still has room inside for a couple of full-sized flash chips and a controller IC, while a microSD has to cram all of that into a fraction of the volume. More room for circuitry = more speed.

I could certainly believe that inherent limitations of the flush-fit size would make it tough to max out a UHC-II bus, but there are UHC-II microSD cards on the market that are at least faster than what the UHC-I bus is capable of. Since the Transcend device is only UHS-I all we can really say about the speed is that it's pretty much maxing out its bus.
 
Bought one of those for my 2021 Macbook Pro yesterday. Like many before have mentioned, they are just perfect for files you have already backupped elsewhere but still want to carry with you (and don't need fast read/write speeds, like movies, archived images, music, etc.). I bought them specifically for backing up my iPhone and iPad, though. These backups have used up around 300GB of space on my internal drive in the past and I can finally free this space up on my fast SSD. Since I always carry my iPhone with me even if my laptop stays at home, this is the only backup I need for the phone and just what I was looking for (I don't use iCloud and prefer local backups).
 
Makosuke said:
This picture of an SD card's guts (an older card, but newer ones look similar inside) gives a pretty good idea of why they're faster:

View attachment 1977669

A full-sized SD card may be small, but it still has room inside for a couple of full-sized flash chips and a controller IC, while a microSD has to cram all of that into a fraction of the volume. More room for circuitry = more speed.

I could certainly believe that inherent limitations of the flush-fit size would make it tough to max out a UHC-II bus, but there are UHC-II microSD cards on the market that are at least faster than what the UHC-I bus is capable of. Since the Transcend device is only UHS-I all we can really say about the speed is that it's pretty much maxing out its bus.
Click to expand...
Even Micro SD’s can hit 190MB/s easy
 
JamesMay82 said:
anyone have any long term issues using these? is there a quicker alternative?
Click to expand...

I used something similar to this brand years back on my old MacBook Air when it had the SD card slot still. It was great for a while but then it started having read issues where the computer stopped recognizing it and mounting it as a drive. Due to its odd size, couldn’t put it into an external card reader to get the files off. Essentially I had to wait until one of the days and times the computer felt like reading it, then Immediately offload the data from it before it stops reading the card again. It’s an awesome idea for a card to stay flush and in the slot, but the design makes it less than desirable in the case of a problem trying to get the data off
 
delsoul said:
I used something similar to this brand years back on my old MacBook Air when it had the SD card slot still. It was great for a while but then it started having read issues where the computer stopped recognizing it and mounting it as a drive. Due to its odd size, couldn’t put it into an external card reader to get the files off. Essentially I had to wait until one of the days and times the computer felt like reading it, then Immediately offload the data from it before it stops reading the card again. It’s an awesome idea for a card to stay flush and in the slot, but the design makes it less than desirable in the case of a problem trying to get the data off
Click to expand...
Ah yes! I had that same problem with that port as well. Completely forgot about it. It was very hit and miss if it worked
 
  • Like
Reactions: delsoul
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back