MicroSD write speeds limited to ~20MB/s

[zhenya]

I purchased a 128GB Lexar 633x card recently
http://www.amazon.com/Lexar-High-Pe...p/B00O1M21H8/ref=cm_cr_pr_product_top?ie=UTF8

It is supposed to have write speeds on the order of 40MB/s, but under no circumstance am I getting much more than about 20MB/s - whether in transferring real files or in benchmarks, using the card reader or the usb3 port with the included adapter. Read speeds are good at 60-90MB/s and it's not counterfeit - I've nearly filled the thing and used it heavily for the last few weeks.

Some other reviewers are reporting the same write speeds, while others are showing speeds of 30-40MB/s.

Any thoughts? What write speeds are people getting from other cards?

 

[leeshor]

There are quite a few posts complaining about the Lexar cards. Return it and get a Samsung.

 

[GreyFox7]

I have a couple Lexar's and they have good to excellent Sequential Read speeds which is what they prominently advertise, write speeds are poor and random r/w speeds are poor to really poor.

 

[kundas1]

PFFT, I have the same card and also not getting the speeds they're are bragging! I'm seriously taking this card back! I posted my speeds in another thread and go see how poorly my speeds are with this card.... I can even notice how slow it is when I unzip a file as its slooooow... Lexar cards are so bad nowadays

 

[Compusmurf]

There are no "really fast" MicroSDXC 128GB cards on the market at this time. They are listed by manufacturers "up to 4x Mbs" in non-fragmented SEQUENTIAL writes under perfect conditions. (all about marketing) Your computer does NOT do sequential writes, it does random large block writes in a fragmented file system which destroys those perfect conditions and will always show a reduced speed. 1-30Mbps high end is normal, with most cards in the 15 to 20 range. If you want a faster write capable card, you'll have to go with a 64GB card, those have had a lot longer time to "mature" and have manu's come up with faster controllers for burst writing. Your tradeoff with 128GB is all about size vs speed.

There are only a few companies right now with 128GB cards. Samsung, Lexar, Sandisk, Patriot and Kingston. Sandisk was the first but their first one was super slow and very unreliable with the other brands coming quite a bit later.

If you look up the SD actual specifications, the rating is for minimum random write speeds that the manu has to comply to, and if I remember right, UHS Class 1/SDXC Class 10 is only really rated at 10Mbps sustained.

 

[kundas1]

^^ be that it may be, if you're gonna start boasting about speeds then you better damn well make sure it's near the mark! I'm not saying exactly on, but at least near there...this/these 128GB cards don't even get 1/3 the speeds the companies are saying and that my friend is false advertising and should be illegal and that's what bothers me....

 

[Compusmurf]

From a legal point of view if the test speed is x then it's not false advertising. From a "moral" point of view, it sure is disappointing when a product doesn't live up to your expectations. My favorite is NEW and IMPROVED on things. Is it NEW or was it improved?

It's not false, but it's not true either. Kinda like gas mileage. ha.

 

[zhenya]

Appreciate all the comments folks.

Anyone have benchmarks or screen grabs documenting better speeds from other 128GB cards? Not sure I will bother exchanging this one, but I'd like to know what else is out there.

 

[bugmenot1234]

Only a couple makers make 128gb microsd as of writing.

http://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias=aps&field-keywords=128gb+microsd

And they're all not the best in class in terms of performance.

 

[zhenya]

Only a couple makers make 128gb microsd as of writing.

http://www.amazon.com/s/ref=nb_sb_noss_2?url=search-alias=aps&field-keywords=128gb+microsd

And they're all not the best in class in terms of performance.

Yes, I see that. I went with the Lexar because I'd heard bad things about the SanDisk, and the reviews for the Samsung were all over the map. I do see now that Amazon bunches all the reviews of all sizes and that most of the reviews for write speeds were on the smaller sizes - although if you filter to only 128GB reviews, one guy is still claiming 40MB/sec writes on a SP3 with this card.

No good reviews of the Samsung card I can see to tell what the 128 is really capable of.