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Maximum SD Card speed?

does anyone know the max sd card transfer speed of the pad, and the dock?
i am looking at a 128GB SDXC card (yes, its a lot, but this is replacing a dead laptop for the foreseeable future) , UHS-1 60mb/s, or a 45mb/s one. will the UHS card actually have any benefits in the dock, or simply when transfering data to it from the PC.
many thanks!

I'm currently running a Class 10 (200x) 32 GB SDHC in the dock, branded Dane-Elec. Runs fine. I don't know if it takes 32+ GB cards, though... And to be honest, while heavily dependent on what you actually do with it, for most purposes a high-speed card should suffice...

ishamm said:
does anyone know the max sd card transfer speed of the pad, and the dock?
i am looking at a 128GB SDXC card (yes, its a lot, but this is replacing a dead laptop for the foreseeable future) , UHS-1 60mb/s, or a 45mb/s one. will the UHS card actually have any benefits in the dock, or simply when transfering data to it from the PC.
many thanks!
Click to expand...
Click to collapse
I'm currently using two Sandisk cards:
- microSD class 10 30MBps SDHC Ultra (16GB)
- full SD class 10 SDHC Extreme 45MBps in the docking station (32GB)
They get better speeds than the built-in disk, but it is still not great. It seems to be about 15-18Mbps write for SD, 6Mbps write for microSD and 30-32Mbps read for both (as compared to 12/18 of the internal memory).
The fastest way of moving data still seems to be external USB HDD...
Hope this helps, haven't tried any other yet. I have tried both FAT32 and NTFS though. They seem to give similar results (I had no problems using NTFS on my SD card so far, which is a good sign).

d14b0ll0s said:
I'm currently using two Sandisk cards:
- microSD class 10 30MBps SDHC Ultra (16GB)
- full SD class 10 SDHC Extreme 45MBps in the docking station (32GB)
They get better speeds than the built-in disk, but it is still not great. It seems to be about 15-18Mbps write for SD, 6Mbps write for microSD and 30-32Mbps read for both (as compared to 12/18 of the internal memory).
The fastest way of moving data still seems to be external USB HDD...
Hope this helps, haven't tried any other yet. I have tried both FAT32 and NTFS though. They seem to give similar results (I had no problems using NTFS on my SD card so far, which is a good sign).
Click to expand...
Click to collapse
I haven't used an external drive yet, but I agree with the observation that the transfer speed is not optimal, no matter what card I plug in (I have transplanted a few I normally use in my DSLR just for testing; they are all fast cards, as you can imagine). I transferred several documentaries and a lot of photographs yesterday evening and it took ages, mainly due to the fact that the transfer process hangs up the entire device (!) regularly. It seems to happen after about 70 to 80 MB are read into (temporary?) memory and apparently are only then buffered out to the main storage. Let's hope a custom ROM can straighten this issue out...

Thanks. Given these figures, would you install apps on the main memory, if a 30mbps rated micro sd for best performance?
Sent from my LT26i using xda premium

ishamm said:
Thanks. Given these figures, would you install apps on the main memory, if a 30mbps rated micro sd for best performance?
Sent from my LT26i using xda premium
Click to expand...
Click to collapse
In my case internal memory is faster than microSD. You don't really have the option, unless you play with the filesystem and mount your MicroSD on /mnt/sdcard instead of /Removable/MicroSD. In the Infinity /mnt/sdcard is just a folder within the internal memory by default (many apps use it though, so they had to arrange it this way). I don't think there is any reason to change this, as internal memory seems faster and that's whole 64GB of it (OK, maybe 56 available, but still a lot..).

Perfect thanks, I thought though that there were current issues with I/O speeds until someone could fix it in a Rom. Or has this been addressed in the new firmware?
Sent from my LT26i using xda premium

ishamm said:
Perfect thanks, I thought though that there were current issues with I/O speeds until someone could fix it in a Rom. Or has this been addressed in the new firmware?
Click to expand...
Click to collapse
Hopefully I could tell you in a few days, but honestly I don't think it has (can't try it out yet, as the firmware released is Taiwanese version, and I'm on the World-Wide).
The Infinity is not that far behind other new tablets or rather it's not only TF700's problem, see http://forum.xda-developers.com/showpost.php?p=28416635&postcount=2842
However, after changing the scheduler to sio and doing some tweaks (see my post on it: http://forum.xda-developers.com/showthread.php?t=1758160), it's running pretty smoothly (unless you want to do a lot of CPU-heavy jobs while having huge reads or writes in the background, in this case it can get frustrating, but.. there is no real alternative these days).

d14b0ll0s said:
Hopefully I could tell you in a few days, but honestly I don't think it has (can't try it out yet, as the firmware released is Taiwanese version, and I'm on the World-Wide).
The Infinity is not that far behind other new tablets or rather it's not only TF700's problem, see http://forum.xda-developers.com/showpost.php?p=28416635&postcount=2842
However, after changing the scheduler to sio and doing some tweaks (see my post on it: http://forum.xda-developers.com/showthread.php?t=1758160), it's running pretty smoothly (unless you want to do a lot of CPU-heavy jobs while having huge reads or writes in the background, in this case it can get frustrating, but.. there is no real alternative these days).
Click to expand...
Click to collapse
This. As i've ranted earlier, the new firmware provides fixes for camera issues, not for the I/O the TF700 so obviously suffers from. Having said that, it is not like the tablet in itself is useless as it is -- far from it -- but remains a mystery to me why they didn't spot this in advance (like with the Prime's issues with GPS and wifi), It seems like ASUS develops a device by letting several teams work onindividual components, and, when they get their specific part up and running, just put it together and relese it. I have a distinct feeling that neither device was actually and properly tested.
But, still, I'm pretty happy with the device overall.

I think you need to read this thread:
http://forum.xda-developers.com/showthread.php?t=1767755
From what I see my UHS-1 card that doesn't work is initialized as DDR which means the max speed for the TF700T µSD is 50 MB/s (as that is the only DDR speed).
The full size SD socket uses a USB host so the big question is is it USB 2.0 or 3.0!

All specifications says USB 2.0 for the dock, so I would assume that's correct, even for the TF700 dock.

Asus has finally responded that there is limited UHS-1 support in the µSD slot.
For now you are better off not trying UHS-1 in there. The may come up with a patch...

external memory limits
ishamm said:
does anyone know the max sd card transfer speed of the pad, and the dock?
i am looking at a 128GB SDXC card (yes, its a lot, but this is replacing a dead laptop for the foreseeable future) , UHS-1 60mb/s, or a 45mb/s one. will the UHS card actually have any benefits in the dock, or simply when transfering data to it from the PC.
many thanks!
Click to expand...
Click to collapse
Careful there with a 128gig card, I read somewhere that there is a 32 gig upperlimit on recognizing cards and sticks...
tho I do wonder if you formatted it into enough partitions it might read them all?

kokoPedli said:
Careful there with a 128gig card, I read somewhere that there is a 32 gig upperlimit on recognizing cards and sticks...
tho I do wonder if you formatted it into enough partitions it might read them all?
Click to expand...
Click to collapse
If the dock uses a sdhc compatible controller and simply exposes the card as a mass storage device for the system, then there is really no such limit. The SDXC cards which supports >32GB does so due to the SD's FAT specification not for actual addressing and such.
SDXC cards are accessible as SDHC but standard specifies ExFat as default filesystem. This may not work on units not compatible with ExFat, but a reformat will fix that. In the TF700T's case we have already seen users use 64 GB cards breaking that 32GB barrier.
We have also seen the TF700T mount ExFat, although it seems to fallback to NTFS.
The thing he should be carefull of is UHS in the µSD socket as it's still wonky.
In the dock I suspect a UHS card will simply be treated as a normal SDHC card, but UHS cards usually have better class speeds so may be a benefit even with the dock doing USB2.0 hosting.
Edit:
To back up my claims see here...
http://kb.sandisk.com/app/answers/detail/a_id/2520/~/sd/sdhc/sdxc-specifications-and-compatibility

Your SD card likely isn't the problem

I was going to post this in response to a couple of people in the development sections but my post count is too low so I'll post it here instead.
The SD slot in this phone seems to have an issue with corrupting SD cards, I've had to format both my old and new SD card multiple times with this phone as it becomes unusable every few days. I'm not versed enough in hardware to know if this is a bad connection between the SD slot and the "motherboard" of the phone. I've seen a number of people have their SD cards go bad with this phone and I assume that means we had a manufacturing issue. It would be really cool if a hardware hacker experiencing this issue could take a look inside and confirm whether or not the hardware is connected correctly.

Well, perhaps there's a high number of bad readers....
I've had the same card in my Q since the day I got it (mid-September), no issues.

Mine wouldn't read the day I swapped up from My Epic 4g Touch to This phone, So I popped in an sd reader backed up my data then let the Moto format it, no issues sence

Curious to know what class of card you guys are running. I've been running a Patriot class 10 but my previous was a class 4 without branding that came with my old Transform.
I'm really hoping that I just had my old SD card die at a bad time and that my newer SD card was just sent bad. Today I couldn't get the card to read from the SD slot in my computer, and it would not be cool if my phone caused it to become that way.

Solust said:
Curious to know what class of card you guys are running. I've been running a Patriot class 10 but my previous was a class 4 without branding that came with my old Transform.
I'm really hoping that I just had my old SD card die at a bad time and that my newer SD card was just sent bad. Today I couldn't get the card to read from the SD slot in my computer, and it would not be cool if my phone caused it to become that way.
Click to expand...
Click to collapse
Class 10 Maxell
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=2074251
No issues here. I tossed the crappy class 2/4 that shipped with my Epic long ago.

Well I found an extra class 4, 2 GB SD card lying around the house when I was cleaning today. It may be that the local shipment of phones was bad, so if this SD card goes on me then I'll try exchanging the phone in another town just to be safe.
Just out of curiosity does anyone know whether Sprint orders enough phones for replacements with their original shipments? I'm not from a very large town so I'd imagine they would keep replacing with phones from the same batch.

I've got a Samsung 32GB class 10 mSD.
Nearly everytime I reboot my Photon Q it says "SD Card is damaged".
Go into settings, Mount SD Card once or twice and it works.
I've read, that other Android Devices have also problems with that size of SD Cards. (Google)
I had also problem in recovery restoring a backup, the restore process didn't went correctly
(said that everything was fine), had to use my 2GB mSD, which worked nicely and the backup also.
So I think it's an android/kernel issue than a hardware issue.

I have noticed that I get the corrupt sdcard error everytime I try to use the "mass storage" or "media device" setting with Windows.
I use Ubuntu 99% of the time and leave it connected in "camera" mode, have never had that pop up like that...
I usually just use ADB to copy everything anyway so I do not miss the "mass storage" mode at all.

Just had a 16gb class 10 microcenter branded card go belly up on me. Phone just all of a sudden said it was removed and now nothing seems to recognize the thing. The mount option is completely greyed out, and does the same on my note 10.1 if i pop it in there.
When your cards have gone did they completely disappear and refuse to read?
Sent from my XT897 using xda app-developers app

I wonder if it's the c10 cards...
You guys really shouldn't be using high class cards in a phone - there's really no benefit, as phones use SD card's very differently from camcorders or cameras...
On my ooooold phone, anything above Class6 was bad juju. I have always had class4 or lower cards, no fried cards (yet... lol)

kinda what I am feeling too. Not sure what class card I have but it was just a cheap 32gb from wallmart... Only had that error pop up once with this one though, and that was after trying to use usb storage.
Sent from my XT897 using xda premium

arrrghhh said:
I wonder if it's the c10 cards...
You guys really shouldn't be using high class cards in a phone - there's really no benefit, as phones use SD card's very differently from camcorders or cameras...
On my ooooold phone, anything above Class6 was bad juju. I have always had class4 or lower cards, no fried cards (yet... lol)
Click to expand...
Click to collapse
Class 10 shouldn't make a difference to a device. The class/speed only comes in to play when transferring data from/to a computer, which will be faster on Class 10 vs Class 4 or 6.
Sent from my PC36100 using Tapatalk 2

arrrghhh said:
I wonder if it's the c10 cards...
Click to expand...
Click to collapse
As best as I can tell, thats a negative. Ive been running with a 32GB class 10 since around when the phone was released, and Ive had no issues. Quite surprising on its own, seeing as I abuse the poor thing. True that class 10 arnt useful for the phone specifically, but some shops only carry class 10 cards.
@hfase
I dont seem to have any issues with mass storage, with ~1GB written a day. Im quite curious as to why some people have this issue.

ADegtyarev said:
As best as I can tell, thats a negative. Ive been running with a 32GB class 10 since around when the phone was released, and Ive had no issues. Quite surprising on its own, seeing as I abuse the poor thing. True that class 10 arnt useful for the phone specifically, but some shops only carry class 10 cards.
@hfase
I dont seem to have any issues with mass storage, with ~1GB written a day. Im quite curious as to why some people have this issue.
Click to expand...
Click to collapse
Maybe it's all down to the quality of the actual card itself?
Perhaps the cheaper no-name / off-name brands have a much higher failure rate....?
I'm not really sure, short of actual hardware issues on the device.

AW: Your SD card likely isn't the problem
Well here is my experience:
I am using a new san disk 32GB class10 micro sdcard. It was never format ed/ used before. The q itself formated the disk.
I have had no problems until using the twisted asanti prebuild
Version. Since then I only got problems with the qu saying the sdcard would be corrupt, after reboot. ( I expected some additional wired things, like the currents widget, which I deleted before reboot reappeared). So I would suggest it is an error in un mounting the sdcard before shutdown, which causes this failure.
Since I usually do not reboot the phone expect for flashing new roms, I had no trouble since then.
Hope this might help to further circle the problem, and maybe find a solution for this.
Sent from my awesome XT897

Since CM10 I haven't noticed any SD-Card issues, but I have the feeling, that there are some issues, which aren't detected.
In the last few days my CM10 was acting weird.
1. The gallery (together with the camera app, 2in1 app) disappeared in the App Drawer (was still in /system/app) and didn't appear again after overwriting gallery2.apk again.
2. The Google Weather App had a graphical issue, so I was sure, that there was a flash issue by restoring ASA14 and flashing CM10 (from SD-Card!).
I solved this issue in copying the nandroid backup and CM10 to the phone and flash it from there.
I have tested my SD-Card in my external cardreader, it had no issues in doing so.
My guess is, that the SD-Card needs more power than the Photon Q can give and is losing some read/write commands.

arrrghhh said:
Maybe it's all down to the quality of the actual card itself?
Perhaps the cheaper no-name / off-name brands have a much higher failure rate....?
I'm not really sure, short of actual hardware issues on the device.
Click to expand...
Click to collapse
I think This may have hit the nail on the head. I have had a couple cheap discount cards die but they really died. Cant even read in the PC and one even got really hot when plugged in. Got a good branded card from amazon and havent had a problem since.

Mordannon said:
I think This may have hit the nail on the head. I have had a couple cheap discount cards die but they really died. Cant even read in the PC and one even got really hot when plugged in. Got a good branded card from amazon and havent had a problem since.
Click to expand...
Click to collapse
I've used better Samsung and Sandisk cards and have had this issue. It just randomly wipes all my data and creates the LOST.DIR with it all in there, but file names are all renamed and would takes years to sort through and try to figure out what is what. All my photos, music, etc.. were basically gone then. It didn't matter that the card was a name-brand or not. I've had the issue with several cards.

I constantly have this problem as well, and I've found that mounting the SD card with a reader or in another phone in a Linux environment fixes it for the most part. I think files still get lost, but you get most of what you had back.

I got a 32GB UHS1 card last week and it hasn't had a problem.

[Q] What to do about a slow SDcard affecting performance?

I have just benchmarked my 8G removable storage card, and got only 1.31MB/s write speed. The two internal cards got 1.73MB/s and 1.47MB/s respectively. Is this slowing down my system? I often notice that Elixir's widget shows that the system is using the disk intensively (shortcut to top shows iowait above 50%). What can I do about this?

gromky said:
I have just benchmarked my 8G removable storage card, and got only 1.31MB/s write speed. The two internal cards got 1.73MB/s and 1.47MB/s respectively. Is this slowing down my system? I often notice that Elixir's widget shows that the system is using the disk intensively (shortcut to top shows iowait above 50%). What can I do about this?
Click to expand...
Click to collapse
set cache
optimal set is 2048
https://play.google.com/store/apps/details?id=com.sdincrease.it

Last updated May 17, 2011...for Android 1.6 and up? :silly: I'm not sure this would really help. Setting the cache size would help to optimize for speed. It wouldn't help poor performance.

gromky said:
I have just benchmarked my 8G removable storage card, and got only 1.31MB/s write speed. The two internal cards got 1.73MB/s and 1.47MB/s respectively. Is this slowing down my system? I often notice that Elixir's widget shows that the system is using the disk intensively (shortcut to top shows iowait above 50%). What can I do about this?
Click to expand...
Click to collapse
i would buy a higher class card.
maybe my memory is off but that write speed seems really low, unless you have a class 2 card, then its still low.

bweN diorD said:
i would buy a higher class card.
maybe my memory is off but that write speed seems really low, unless you have a class 2 card, then its still low.
Click to expand...
Click to collapse
It's a Kingston 8Gb "MicroSD HC" SDC4. I don't know if it's class 2 or not.
Also, does it really make a difference? If the system is thrashing the disk, then all the usage should be in the two internal sdcards. Is that right?
What kind of card would be a good replacement?

gromky said:
It's a Kingston 8Gb "MicroSD HC" SDC4. I don't know if it's class 2 or not.
Also, does it really make a difference? If the system is thrashing the disk, then all the usage should be in the two internal sdcards. Is that right?
What kind of card would be a good replacement?
Click to expand...
Click to collapse
Its a class 4 which means the r/w speed should be higher than you are reporting. IMO either your phone can't support any higher speed or something is wrong with the card.
The class of the card does matter and can cause some operations to be slower in comparison to say a class 10 card.
I don't know why your phone is thrashing the card, unlikely normal, but it could be. Other possibilities are issues with the phone software, or issues with the card like partial corruption or bad sectors, even bad pics or vids can cause the system to scan the card too much.
Look in battery stats and see if the media scanner usage is high, this would indicate a corrupt file.
Alternatively, I would test the card for errors. Grab a card tester from Google search, put the card in your PC, copy the entire contents to your PC, run the test program. If no errors, put the card back into the phone and format, then copy back your files.
If errors, get a new card. I have always bought sandisk class 10 from an eBay reputable seller. Read up on the seller wherever you get it from so you don't get a fake card.
Sent from my LG-VS980 using XDA Premium 4 mobile app

bweN diorD said:
Its a class 4 which means the r/w speed should be higher than you are reporting. IMO either your phone can't support any higher speed or something is wrong with the card.
The class of the card does matter and can cause some operations to be slower in comparison to say a class 10 card.
I don't know why your phone is thrashing the card, unlikely normal, but it could be. Other possibilities are issues with the phone software, or issues with the card like partial corruption or bad sectors, even bad pics or vids can cause the system to scan the card too much.
Look in battery stats and see if the media scanner usage is high, this would indicate a corrupt file.
Alternatively, I would test the card for errors. Grab a card tester from Google search, put the card in your PC, copy the entire contents to your PC, run the test program. If no errors, put the card back into the phone and format, then copy back your files.
If errors, get a new card. I have always bought sandisk class 10 from an eBay reputable seller. Read up on the seller wherever you get it from so you don't get a fake card.
Click to expand...
Click to collapse
Ah, so it shouldn't be this slow. Class 4 should be enough. The problem shouldn't be my phone, it's a Xiaomi Hongmi/Redmi and it was manufactured last year.
I've checked the battery usage and media scanner isn't listed. Do you know how I can figure out which program is thrashing the disk?
It's a microSD card so it won't go in the computer. I have a USB adapter somewhere, but those greatly slow performance.

gromky said:
Ah, so it shouldn't be this slow. Class 4 should be enough. The problem shouldn't be my phone, it's a Xiaomi Hongmi/Redmi and it was manufactured last year.
I've checked the battery usage and media scanner isn't listed. Do you know how I can figure out which program is thrashing the disk?
It's a microSD card so it won't go in the computer. I have a USB adapter somewhere, but those greatly slow performance.
Click to expand...
Click to collapse
Class 4 should be running at 4mb or better.
Sorry I don't know how to tell what is causing the excessive r/w on the card.
Most newer PC's have a SD card slot, you just need the adapter that frequently comes with the card.
The performance through USB isn't really relevant, that's not the purpose of connecting it to the PC. You want to check it for errors or damage. A slower connection method will just make the process take longer.
Just follow my previous post instructions and backup your files first. I think the checking program is going to format the card to run its tests, its been a long time since I used it, I don't remember exactly.
Later when I get home I can help you find a program if you haven't found a good one by then.
Sent from my LG-VS980 using XDA Premium 4 mobile app

gromky said:
Ah, so it shouldn't be this slow. Class 4 should be enough. The problem shouldn't be my phone, it's a Xiaomi Hongmi/Redmi and it was manufactured last year.
I've checked the battery usage and media scanner isn't listed. Do you know how I can figure out which program is thrashing the disk?
It's a microSD card so it won't go in the computer. I have a USB adapter somewhere, but those greatly slow performance.
Click to expand...
Click to collapse
ok, this is what i used last time http://sosfakeflash.wordpress.com/2...standard-in-detecting-usb-counterfeit-drives/
there is a "direct" download link a little down the page.
the tool was made for checking for fake cards, but if you give it a quick read, you will see its going to check for errors, report the condition of the card, and more.
hope that helps.

Do Micro SD cards slow down overall/general phone performance?

Hello!
I just had a few questions regarding Micro SD cards and I wanted to get some of your opinions on the matter.
I work in the mobile phone industry. My coworker and I were discussing (maybe a bit of arguing) the inclusion of the SD card slot inside the Galaxy S7 and whether it's a good idea. He's under the very passionate impression that Samsung made a huge mistake incuding the slot in the S7, which is very contrary to my opinion.
His reasoning is that having an SD card in your phone decreases general speed/performance and that it's an obsolete feature. I've never had an issue with SD cards in my experience. I can perhaps imagine that the class of SD card may make a slight difference. I know transfer speeds vary but I don't agree that it slows the phone down during normal processes.
Do you think the SD card or just memory cards in general will eventually become a thing of the past or do you think that expandable storage will always be a viable option at least in the forseeable future?

Question S-L-O-O-O-W external microSD memory

I just bought an A53 , stepping down from "flagships" because the newest ones all lack expandable storage.
This feature is a MUST for me!
I've found the A53's interfacing to the card slot to be so EXTREMELY slow, to make it unusable!!!
Anyone else seeing this as well?
(I'm using a 1TB SanDisk - about 75% full - that worked quite well in my previous phone)
Is it the Exynos chipset (vs. Snapdragon previously) that is causing the difference?
Is anyone here using a large capacity microSD without any noticable speed issues?
Anything I might do to improve the situation???
(Aside from sending the phone back?)
And if I have to resort to that - recommendations on a good pgone w/ expandable storage - up to 1TB)?
(Many only specced to 256 GB)

What is slow? From internal memory to SD card or via Cport to SD card?
Is it a V30 rated card ie Sandisk Extreme?
On my N10+ with a V30 rated Sandisk:
Internal write 3.4-4gb @ minute
External write 1-2.2 gb @ minute, I believe it was.
An external transfer takes about 3.5 hrs for 400gb of data. Rates very somewhat depending on file structure and type.
The .5tb Sandisk Extreme is slightly faster. Both stream high res vids with no issues. Zero problems with both.
Once in the phone format card with phone before using. Do not remove the card once installed; instead do data transfers via the Cport. Do Not use in other devices unless formatting in new device first as it can cause card corruption. I was able to transfer my older .5tb card to my new N10+ without a format with no issues. However in general I don't recommend this practice. A corrupted card is a very rude surprise.
A used N10+ in good condition trumps a newer midrange Samsung especially if 5G and variable refresh rate display aren't important to you. It's a beast that runs like a she bat out of hell.

Many thanks, Blackhawk for your prompt and helpful reply!
Simply reading from the SD card, and getting a listing of files in s folder is very slow.
Here's an example:
Moving files from one folder to another on the SD card...
9634 files, 12.7 GB ; has taken over 29 HOURS
That's 2 hours per gigabyte.
Other transfers from internal memory to SD are also very slow, and often fail
depending on the file manager I try to do it with.
The card is a SanDisk 1TB Ultra MicroSDXC UHS - 120MB/s, C10
and as I mentioned, it has worked fine on my previous phone.
I've tried several different file managers with varying results.
They vary from completely inoperable to barely functional.
(The 2 hours per gigabyte is the BEST I could come up with )
The card was formatted in the old phone, and some transfers in and out were with a Windows PC in between.
I'll try offloading the contents to another drive and formatting in the A53 before copying back again.
5G is important - and a Note 10+ 5G would be an available option - but only available as refurbished now.
I may go there if the reformat experiment doesn't pan out.
Thanks again!

This is the one that you wanted for best speed. V30 rated. Even so your transfer rates aren't even near the ballpark.
Try reforming the card in the phone. Maybe a bad card; always buy from a reputable source, if it seems too inexpensive it's likely a fake. They are out there! B&H Photo, Western Digital and Amazon are good sources.
Unlikely it's the phone but check the contacts and clean the SD card contacts with anhydrous isopropyl alcohol. Never touch the contacts.
I don't recommend the N10+ 5G variant as it's a first generation 5G and will likely chew up battery life. 4G works well enough to stream vids and many sites cap their downloads making 5G irrelevant. New N10+'s may still be available if you look hard enough. I picked up one 9 months ago, not cheap but in a factory sealed box, perfect condition and running on Android 10.
Although I prefer Pie, 10 is ok, 11 not so much because scoped storage is fully active, 12 I won't touch. Pie is relatively secure unless you do stupid things. This device in my hand load is over 2 yo still running fast and stable.
Snapdragon is the preferred variant (better chipset and heat sink) unless you want to root.
The N10+ has maybe the best display available in terms of white point, color calibration/accuracy and gamma. The variable refresh rate displays are extremely hard to calibrate across the multiple display rates/brightness levels. As such the N10+ likely beats out even the newest Samsung flagships in these specs. Color accuracy is important to me; without accurate color calibration the gamma calibration sucks.
I deliberately chose a new N10+ over the N20U because of the above plus better form factor, the spen is on the right side, better SOT and reliability. The only repair my N10+ has had is a replacement battery. It looks, feels and runs like new. It's a gorgeous beast even today and a blast to use.