I’m wondering to what extent the SDXC card slot on the 2019 27” iMac can serve as another solid state drive? Guessing that’s not the intended use, but I can’t think of any reason why data could not be stored on a SDXC card kept in the slot? Comments?
Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
SDXC card slot as additional storage?
- Thread starter remiller
- Start date
-
- Tags
- sdxc card slot
- Sort by reaction score
Since posting the question, I searched the forum and found folks successfully using a card that way in a MacBook, etc. (I should have searched prior to posting. Apologize for wasting the bandwidth.) I guess the question then becomes is there a limit to the capacity of the card that the Mac can address? This approach to having files readily at hand without consuming internal SSD space seems like a good thing to me.
Yeah the reader is UHS-I which is only around 100MB/s and generally aren’t made for as many write cycles. Mechanical drives are actually faster these days between 150-200MB/s. The SSD in the last iMac was about 2,800MB/s so this would should be at least that fast, if not faster. You’d be better off if you want to save money getting an enclosure for a 2.5” SSD at 550MB/s or a blade enclosure at around 1GB/s.
I don't see any problems using it as "cold storage" or for brisk use.
Besides the speed as mentioned, the other issue is heat. I know my thumb drives get hot after a longer transfer.
Transfer speeds will get slower throughout the process.
If you're trying to use it as an active storage, get the cards with the pro/high endurance label. These are normally for continuous video recording so they will have better resistance to heat and memory life.
Besides the speed as mentioned, the other issue is heat. I know my thumb drives get hot after a longer transfer.
Transfer speeds will get slower throughout the process.
If you're trying to use it as an active storage, get the cards with the pro/high endurance label. These are normally for continuous video recording so they will have better resistance to heat and memory life.
This. I totally agree. There is no way I would use a SDXC card to store valuable data without having backups. I have had SDXC cards fail out of the blue. If you're thinking about ordering a new 2019 iMac, spend the extra bucks and get a large SSD instead; at least 1TB.
Even the fastest SD cards aren't going to be "that fast" in the Mac's slot.
You'd do better to buy a USB3 SSD, and use that.
No matter what you choose, as mentioned above, if there's anything critical on it, you'll STILL want to "back it up" to another drive.
You'd do better to buy a USB3 SSD, and use that.
No matter what you choose, as mentioned above, if there's anything critical on it, you'll STILL want to "back it up" to another drive.
Well, it will work - plenty of Android phones, Raspberry Pis, set-top boxes etc. use SD cards for this. The speed and durability issues brought up by others in this thread are valid, though. Certainly not a backup solution - you'll need some sort of external HD/SSD, NAS or cloud storage anyway.
I'd say the best application was something like a personal media library - bulky files, infrequently updated and .mp3s and .mp4s compressed for streaming won't care about the slow speed and (maybe) no animals are harmed if you loose it. If you have an iMac with a small-ish SSD and just want tunes while you work, it doesn't sound like a bad idea for the price.
Sequential read & writes: yes.
Random read & writes: no.
The question is: what do you need more often? And the answer is random. Sequential reading and writing is very rare on a modern computer. Booting the OS, launching applications, or loading and saving files are always random read & write operations because the data required is never neatly organized in a sequential strip of blocks but spread all over the rotating platters. That's why an SD card can feel much faster than a mechanical hard drive: its random read & write times can be hundreds of times faster than those of a mechanical hard drive.
That said I absolutely agree with the reliability statement made before. Make sure to keep a backup copy somewhere and make sure to make regular backups of those files. SD cards are much more likely to fail than SSDs or mechanical hard drives.
While I agree with the reliablity statements in general, I have to take issue with the general tone of those comments. If data is valuable you need backups, period. Even the internal SSD or HDD is no where near reliable enough to not need a backup. Just include the SD card in your backup routine. Keep in mind that these cards are the standard storage for all modern digital cameras where they get heavy use and have proven rather reliable.
I've used micro SD cards for various sizes as additional storage on my old Dell Venue 8 Pro (8" Windows tablet) and my current Surface Go has a 128Gb card. Both devices are designed to store the cards permanantly, they mount flush or resessed. I genereally store pictures, documents, and videos on the cards along with a few utilities. In the ~5 years of daily use between the 2 devices, I've never had an issue. The first card in the Dell was used for 2+ years before being replaced with a larger card. The cards are slower than the internal drives (eMMC in the case of the DV8p and NVMI in the case of the Go), but they have still been up to the task for watching 1080p videos.
I've used micro SD cards for various sizes as additional storage on my old Dell Venue 8 Pro (8" Windows tablet) and my current Surface Go has a 128Gb card. Both devices are designed to store the cards permanantly, they mount flush or resessed. I genereally store pictures, documents, and videos on the cards along with a few utilities. In the ~5 years of daily use between the 2 devices, I've never had an issue. The first card in the Dell was used for 2+ years before being replaced with a larger card. The cards are slower than the internal drives (eMMC in the case of the DV8p and NVMI in the case of the Go), but they have still been up to the task for watching 1080p videos.
I use a SD card to hold my iTunes music library to save space on the speedy internal 2TB SSD. Since it is inconvenient to reach the card slot on the back of the 2017 iMac, I use a separate SDXC-II/CF card reader that is easily accessible in front. There is no speed issue with music files.