The SSD Review The Worlds Dedicated SSD Education and Review Resource | 
TEMPS, SUSTAINED WRITES AND TRUE DATA TESTING
TEMPERATURES
Two characteristics that became very important with the introduction of CFexpress as a mainstream storage medium were temperature and sustained write speeds. We measure temperature by monitoring and updating a Crystal DiskInfo Benchmark while a large 85GB 8K file transfer is being performed. This is the extreme of what one might see in this environment. An important aspect to remember is that the temperature results we obtain are the extreme. They are the hottest the card got during any period of our testing which was constantly monitored. It does not speak to the median or typical temperatures one might expect which would be around the low 30°C mark.
With this in mind, the highest temperature reached with the Lexar Professional 4.0 CFExpressB 1TB Memory Card was 67°C and there was no throttling of this card any time during our testing.
SUSTAINED WRITE PERFORMANCE
We determine sustained write performance by transferring a 85GB 8K media folder from the PC to the CFexpress Type B card. This test is vital to those looking at digital storage for high end 4K and 8K video recording.
The Lexar Professional Gold 4.0 CFExpressB 1TB Memory Card held a sustained write speed average of 1510MB/s throughout the transfer which is well above the minimum standard of 400MB/s.
REAL WORLD FILE TRANSFER COMPARISON
Our Real World File Transfer Test is conducted through the transfer of data from one spot on the test drive to another to give us the truest of transfer speed results for that device.
The Lexar Professional 4.0 Gold placed second right behind the PG Gold 4.0 with respect to data transfer.
Lexar also has a memory card utility software called ‘Lexar DiskMaster’ which is a free download and available here. It provides a number of features to enable one to maintain the performance of their CFExpress Memory Card.
REPORT ANALYSIS AND FINAL THOUGHTS
With respect to USB 4.0 CFExpress Type B cards, we have tested three to date, two Pro Grade and the Lexar Professional Gold 4.0 we are looking at in this report. All three stand well above previous Gen cards while all three are very close in their comparative testing of one another. The Lexar Professional seems to push just a bit higher in sequential performance at 3576MB/s read and 3449MB/s write, while the ProGrade Iridium excels by a wide margin with respect to read and write IOPS.
Something we cannot seem to get our hands on, although it is available, is the 4TB version of this card…but that is a given as it is a very niche and high value item. Lexar stands out with its lifetime warranty. Checking Amazon, we can find the Lexar Gold 4.0 Memory card priced at $129.99 (240GB), $189.99 (512GB), $329.99 (1TB), and $599.99 (2TB). We could not find the 4TB version on Amazon at the time of this report however we are well aware that it is priced North of $1100.
Last but not least, our testing of all CFExpress Type B 4.0 cards to date has demonstrated that they run rather warm, just above 60°C during high file size data transfer. We haven’t experienced any throttling whatsoever in result, however. Do we recommend them? We wouldn’t use any other! Gold Seal.
CHECK LEXAR PRO CFEXPRESS B GOLD 4.0 PRICING AT AMAZON
