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Lexar Professional 633x U3 64GB SDXC Memory Card Review

Lexar Professional 633x 64GB UHS-I U3 SDXC Memory Card Front

Introduction

The new Lexar Professional 633x SD cards are an update to the 600x SD cards. The cards meet the UHS Speed Class 3 (U3) specification that is given to cards that support 30MB/s or higher continuous write speed, a requirement when recording 4K video.

The Lexar 633x cards are quoted at 95MB/s read and 45MB/s write write speed, essentially the same as the 90MB/s read and 45MB/s write of the 600x cards they replace. The 633x cards are available in 16, 32, 64, 128 and 256GB capacities (the 16GB card has 20MB/s write speed). This review is for the 633x 64GB SDXC card.

Lexar Professional 633x 64GB UHS-I U3 SDXC Memory Card Back

Performance

In card reader benchmark tests the 64GB 633x card measured 96.0 MB/s sequential read speed. This is essentailly the same as the Lexar 600x 64GB card that measured 96.6 MB/s. Sequential write speed peaked at 69.3 MB/s, well above the 45MB/s specified by Lexar, but basically the same as the old 600x 64GB card that mesaured 68.6MB/s.

Card: Lexar Professional 633x U3 64GB
Benchmark: CrystalDiskMark 3.0.3 x64
Program settings: 1000 MB, 5 passes, random test data
Operating system: Windows 8.1 Pro
Motherboard: Gigabyte GA-Z77X-UD3H
Processor: Intel Core i7-3770K @ 4.40GHz
RAM: 32GB DDR3 1600

Lexar Professional 633x U3 64GB
Card Reader Benchmarks
Seq.
Read
1000MB
MB/s
Seq.
Write
1000MB
MB/s
Rand.
Read
512KB
MB/s
Rand.
Write
512KB
MB/s
Rand.
Read
4KB
MB/s
QD1
Rand.
Read
4KB
IOPS
QD1
Rand.
Write
4KB
MB/s
QD1
Rand.
Write
4KB
IOPS
QD1
Rand.
Read
4KB
MB/s
QD32
Rand.
Read
4KB
IOPS
QD32
Rand.
Write
4KB
MB/s
QD32
Rand.
Write
4KB
IOPS
QD32
Lexar LRWM04U-7000 UHS-II Reader96.01568.92687.16333.0076.0501477.10.880214.97.9441939.30.942229.9
Lexar Professional Workflow SR2 UHS-II95.44768.92686.58826.2065.8451426.90.919224.57.8851925.11.190290.6
Delkin Dual Slot SD UHS-II and CF Card Reader94.96357.65287.54226.7755.9131443.60.785191.57.9191933.40.929226.9
Kingston FCR-HS4 Card Reader94.88569.27287.19225.6635.8971439.80.908221.87.8701921.50.945230.7
Kingston MobileLite G4 UHS-II94.57769.03186.96124.5646.0481476.60.919224.57.9001928.71.082264.2
Lexar Professional Dual Slot UHS-II Card Reader94.48367.77252.53021.8594.9951219.60.704171.96.8871681.50.947231.1
Transcend Multi-Card Reader RDF994.45869.10385.92134.2735.8931438.80.910222.27.9991952.81.122273.8
Delkin Travel Reader94.36465.58983.8447.1485.8341424.31.007245.97.8761922.91.277311.7
Lexar Professional Workflow SR194.12768.90484.34027.9845.5551356.20.913223.07.1261739.71.188290.1
SanDisk Extreme Pro UHS-II SD Reader/Writer93.97568.98186.74535.1875.8591430.50.919224.37.8561918.01.103269.2
Transcend Multi-Card Reader RDF8 Black93.96769.28684.77230.9015.5081344.80.31576.96.5981610.91.120273.4
Lexar Professional Dual Slot Reader93.90869.32784.95425.9375.5751361.00.932227.67.3831802.41.188290.0
Transcend SD Card Reader RDF5 Black93.72368.72884.31326.6984.5201103.40.805196.65.5781361.90.862210.5
Delkin Universal Memory Card Reader93.08368.32983.92821.9725.5711360.20.849207.27.4011807.01.072261.8
Sony MRW-E90 XQD 2.0 / SD UHS-II Card Reader92.34566.90383.02817.2355.5131345.90.867211.77.4311814.10.902220.3
SanDisk ImageMate All-In-One USB 3.091.55568.28076.71726.0193.898951.80.824201.14.5131101.70.988241.3
Kingston Multi-Card Reader FCR-HS389.10462.49360.7826.9535.7921414.01.008246.27.7871901.00.953232.6

In digital camera tests the write speed measured 59.1 MB/s in the Canon Rebel T6s. Additional in camera test results will be added to the chart below.

Lexar Professional 633x U3 64GB
Tested in Camera
Write Speed
(MB/s)
Canon 80D61.1
Fuji X-Pro259.2
Canon Rebel T6i/T6s59.1
Canon 5Ds55.4
Nikon D50054.3
Canon 5D Mark IV51.9
Fuji X-T1048.3
Olympus PEN-F39.8
Pentax K-3 II36.4
Sony A7R II34.7
Sony A630032.8

Cameras tested with this card: Canon 5D Mark IV, Canon 5Ds, Canon 80D, Canon Rebel T6i/T6s, Fuji X-Pro2, Fuji X-T10, Nikon D500, Olympus PEN-F, Pentax K-3 II, Sony A7R II, Sony A6300

While the label is new, the actual read and write performance of the 633x card is pretty much the same as the previous 600x cards. The write speed was well above specification, but short of the higher write speeds offered by Lexar's 1000x and 2000x UHS-II cards. The UHS-II cards are backwards compatible with UHS-I cameras and devices but maximum speed is limited to about 95MB/s read and 90MB/s write in UHS-I mode.

Lexar Professional series memory cards have a limited lifetime warranty and are made in Korea.

The following table contains information encoded in the SD card.

Lexar Professional 633x U3 64GB SD — Internal Card Information
Serial number (PSN)554108375
Product Name (PNM)
Product Revision0.1
Manufacturer ID (MID)0x000028
OEM ID (OID)BE
Manufacture Date (MDT)03/2015
Total capacity64,087,916,544 bytes

Available sizes and prices

Compare prices on the Lexar Professional 633x U3 card. The lowest prices are highlighted in the table below. Prices are updated daily.

CardSize
GB
Lowest
$ / GB
Prices
AmazonB&H PhotoAdorama
Lexar Professional 633x U332$1.03$32.95Check priceCheck price
Lexar Professional 633x U364$0.73$46.90Check priceCheck price
Lexar Professional 633x U3128$0.52$66.90Check priceCheck price
Lexar Professional 633x U3256$0.39$100.02$105.98$105.98
Lexar Professional 633x U3512$0.43$220.00$220.00$220.00