LexarHigh-Performance MicroSDXC 633x 64GB UHS-I U1 w/USB 3.0 Reader Flash Memory Card (old U3 version) LSDMI64GBBNL633R

I had the opportunity to compare the performance of the fastest microsd cards currently available from top manufacturers. All cards mentioned in this review are obtained from Amazon during the last week or two except when noted otherwise.Test Setup:Lexar Professional workflow UR1 microsd card reader was used for all tests except when notedCrystalDiskMark 5.0.2 x64 was used to produce all the test results and was set up with 2 passes and 100MB read/write sizeAll cards up to 32GB are formatted as FAT32 with 32KB allocation unit size, all 64GB cards are formatted exFAT with 128KB allocation unit sizeTest Results (Numbers are Sequential Read, Sequential Write, 4K Random Read, 4K Random Write in MB/s, speeds greater than 10MB/s were rounded to the whole numbers)16 GB AlphabeticallyLexar 633x** -- 88, 25, 8.7, 1.2 <== the listed productPanasonic U3** -- 93, 42, 11, 0.7Sandisk Extreme Pro -- 95, 80, 7.6, 2.632 GB AlphabeticallyDelkin U3 -- 93, 59, 11, 0.6Kingston 90R/80W -- 93, 58, 11, 0.6Lexar 1000x -- 90, 57, 10, 1.4Lexar 1000x with Bundled Reader* -- 148, 60, 10, 1.4Patriot EP -- 90, 35, 10, 0.6PNY Turbo Performance -- 91, 55, 6.9, 0.9Samsung Pro gray -- 92, 82, 10, 3.6Sandisk Extreme Pro -- 94, 87, 9, 3.0Sony up to 95MB/s -- 91, 51, 4.8, 0.9Transcend Ultimate 633x -- 93, 85, 8.1, 1.464 GB AlphabeticallyDelkin U3 -- 94, 27, 13, 0.3Kingston 90R/80W -- 94, 25, 13, 0.3Lexar 1000x -- 92, 56, 12, 1.5Lexar 1000x with Bundled Reader* -- 153, 66, 11, 1.7Patriot EP -- 81, 22, 11, 0.6PNY Turbo Performance -- 92, 54, 6.9, 0.9Samsung black -- 82, 20, 8.8, 2.1Samsung Pro gray -- 90, 80, 10, 3.5Samsung Pro+ *** -- 92, 86, 10, 5.3Sandisk Extreme Plus**** -- 92, 58, 10, 2.8Sandisk Extreme Pro - 97, 91, 10, 3.0Sandisk Ultra ***** -- 46, 16, 7.0, 2.1Sony up to 95MB/s -- 92, 49, 5.2, 0.9Transcend Ultimate 633x -- 93, 83, 7.3, 1.4128 GB AlphabeticallyLexar 633x -- 78, 28, 3.3, 1.4 <== the listed productSandisk Ultra -- 92, 19, 6.4, 2.4* The Lexar 1000x card is the only UHS-II card available and tested, the bundled USB reader has extra pins for reading UHS-II card** Came bundled with a device*** Purchased from a large west coast electronics retailer. This card is a new release and not currently available on Amazon. It is different from the gray-colored Pro card**** old model tested, not the current U3 model***** old model testedFastest Sequential Read:All tested cards were able to accomplish > 90MB/s, with the Lexar 1000x able to take advantage of UHS-II speed when using the bundled USB reader and leading the packFastest Sequential Write:Sandisk Extreme Pro, Samsung Pro+, Transcend Ultimate 633xFastest Random Read:Kingston 90R/80W.Fastest Random Write:Samsung Pro+Best overall:Samsung Pro+ and Sandisk Extreme ProOther observations:Performance and price are not proportional when it comes to selecting a microSD card. Some of the worst performing cards in this review also happen to be the most expensive.Not all 633x cards are created equal. The two cards reviewed from Lexar and Transcend are both marked as 633x but vary in performance greatly.4k video recording using action cams and drone cameras have a typical bitrate of 60mbps or 100mbps, corresponding to 7.5MB/s to 12.5MB/s. All cards in this review should theoretically be able to handle this usage easily.Using microsd card as supplemental phone storage potentially could benefit from a faster card,Best Looking Card (if it matters):Sandisk Extreme Pro: Red/Gold with white printLexar 1000x: White/Gold with Black/White printSamsung Pro+: White/Black with a red stripe and Black/White printPNY Turbo: Lime Green/Black with Black/White printUpdate 9/14/2015: Added additional cards to the list.

I have been reading about a disturbing trend, counterfeit sd cards. (if you really know your real product you should be able to spot a bad one, many of the companies rely on their reputation so please give them a chance to help you. After all they may have been duped) You can go to different sites that have a comparison of different cards and their nemesis.Many say that if you don't get the main brand you could get a virus. But what are we to do, we want to keep a memory of our trips, school functions for our kids, or business affairs. I can only tell you what I know about this little micro sd card. It is a high quality, high capacity card.For example: went on a two week trip 747 photos and 18 1min videos later and wasn't even 1/2 full. The card functioned as it should have, the phographer on the other hand.For those that don't understand what all the number and letters on the sd card mean I'll try to help sort it out. I know someone who is a bit more technologically sauve than me may refine the descriptions.Lexar=the brand that you have purchased.The number below the brand, in this case 633x=should indicate the cards fastest read speed.Next move to the 10 in the circle=this is your write speed, in this case 10mb/s (10 mega bites a second) This gives you full HD video recording and consecutive HD recording of stills.32GB=the amount of memory it can hold. It is concidered one of the larger end so estimates are about 8,000 songs, again it's what you put on it, but you shouldn't run out of memory.Micro sd hc=It is a micro sized so you will need an adapter to load it into your computer to add songs, videos etc. HC=High capacity. The total name of sdhc=Secure digital high capacity.3 in the u=a minimum write performance of 30 mb/s lets you record HD video resolution while having the ability to do other functions.Finally the 1=the grade of performance.Hopefully this will help you in choosing the right sd card for the functions you need and the capacity you want. Oh and you can lock the card by sliding the little button into lock, so everything is safe.A good little card!

it’s not working in my dashcam

It's a memory card! I needed a high-capacity card as a backup for another of the same size. I opened the package, filled the card almost completely with data. It worked. No errors. The transfer was quick. The real bonus is that the card comes with a USB 3 mini adapter, which is one of the main reasons I picked this from the many other cards at the same price. Using the mini adapter, the data copying was way faster than it would have been with any other transfer method. Fair price, quick delivery, great little USB adapter.

Great speed when transferring data. Works great with Sony HDR AS100 ActionCam shooting Pro mode at 50mbps5hrs, 23m = (1080/60fps mode/50mps pro recording)11hrs = (1080/60fps mode)Crystal DiskMark 3.03 Bench (500MB)- Sequential -93.68 Read / 57.85 Write*I have the same SDXC card 64GB 644x. For some reason it stopped reading and wouldnt format. Performed a RMA online at Lexar as via their Live Support Chat I sent my card back and they sent me a new one. Lifetime Warranty is superb. So good I decided to buy this 128GB version. The 11 hours of continuous uninterrupted recording I get in my Sony actioncam is just wonderful.

well... a few months after I purchased this card it suddenly began showing up as "write protected" .. with about 60g free I can no longer write to it or delete files. I have tried every trick in the book (from the simple ones such as putting it into a sd card adapter and using the lock/unlock position switch to complex ones like registry hacks. No luck... The card does not allow any changes to it. I would NOT recommend you purchase this card

Mine worked for four months, after which it would not allow writing to it at all (all card readers / operating systems identified it as "write protected"), and has now been accepted for RMA after using their online chat on the Lexar website. They emailed me a suggested fix to try which wasn't appropriate, but otherwise, so far, the RMA process has been faster than others I've tried.