Delkin Black CF Express Type B 512GB Memory Card Review – Incomparable Sustained Write Speeds and Low Temps



Having tested a number of CFexpress Type B cards to date, it is nice to see that high temperatures seem to be becoming the exception rather than the norm.  Delkin Devices tackled temperatures with their 64GB and 128GB CF Express Type B cards earlier on and we demonstrated that achievement in this report. Now check out the updated charts below which add the newest Devices Black CF Express Type B 512GB Memory Card to the mix.

The lower the better and the Delkin 512GB Black CF Express Type B Memory Card literally blows away the competition with its low temperature of 39°C during sustained write data transfer.  This temperature was achieved at a point when others couldn’t resist reaching higher temps. In fact, even now with this card sitting in the PC for several hours, its ambient temperature is all of 29°C which is unheard of for a CFExpressB card.


Our sustained write performance of the Delkin Devices Black 512GB CFExpress Card was 1.43GB/s.  Again…unheard of. We test this by transferring an 85GB 8K media folder to the CFexpress card and obtaining the speed at about the 85% mark once it has leveled off for some time.


With our previous reviews of the SanDisk Extreme Pro and the Lexar Professional CFexpress Type B Cards, we were rather impressed with the sustained performance that we were seeing, topping 1GB/s in fact. The Delkin Black 512GB CF Express Type B Memory Card our top result to date.


This is a great time to see exactly what we mean by differing sustained write performance not being recognizable in normal testing.  Check out the sustained write of the first place card, the Delkin Devices Black, compared to the other end of the spectrum with the ProGrade 1700 Gold at 357MB/s.  Would you believe these have almost exact specs with respect to ‘peak’ performance?  Don’t get me wrong.  As much as that 1700 Gold CFexpress card may be the slowest on the chart, it performs fine in digital cameras, has an excellent reputation… and is an amazing 1TB in size.


For our Real World File Transfer Comparison of the world’s top CFexpress Type B cards, we have included all cards that we have received to date. This 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.


As we can see, the Delkin Devices Black placed third and just behind the ProGrade Cobalt CFExpressB cards.  There is very little difference in the result considering, and it actually becomes moot when we include sustained write performance and temperatures in the overall picture.


Without a doubt, the most important points for consideration when choosing a CF Express Type B memory card for your high end mirrorless digital or video camera just have to be sustained write performance and temperatures.  If not considered, one can spend days trying to figure out why things aren’t working as they should, and the loss of valuable media during this is inevitable.  The unfortunate part is sustained write performance, for the most part, is still hidden in the fine print as are temperatures.  It is unfortunate that we see high sequential read and write performance front and center of all packages when the typical person may never reach that performance in their work.


Delkin has done their homework.  They not only listened to the changing industry needs, but also, to the consumer and media professional.  Their response is the Delkin Devices Black 512GB CF Express Type B Memory Card which is the coolest and fastest on the market right now, all things considered.  We have yet to see another with temperatures as low as Delkin during heavy media workloads and 1.42GB/s sustained writes is unheard of.  Add to this what we hope to be decent pricing once full availability is achieved and an untouchable lifetime warranty with a 48 hour exchange guarantee and there is just not that much to spare.  Editor’s Choice!

Check for Delkin Black CF Express Type B Pricing at Amazon


Delkin Black CF Express Type B Rating

Product Build
Performance and Sustained Writes
Low Temperatures
Lifetime 48 Hour Exchange Warranty
Availability and Pricing

Fastest and Coolest Available!

The Delkin Black CF Express Type B Card runs cooler and faster than any CF Express Type B memory card tested to date. With its lifetime warranty and 48 hour replacement guarantee and decent price point, this will be one of the hottest on the market.

Check Amazon
User Rating: Be the first one !


  1. blank

    I don’t do high FPS bursts so I’m wondering if there is a difference in idle or low activity temperature between a Delkin Black and Power for an R5. Would an optimized 256GB+ Power have the same 45C temp. as the 128GB? I’m assuming the 15GB photo transfer is the closest benchmark to simulate camera to card write speed.

    • blank

      You will be fine. The temps come in with video use for the most part. As well, if you can live with the lower sustained write transfer speeds you are golden.

      • blank

        I just don’t want to feel the grip being warm so if the Power card will be just as cool for light loads than that will be great since I’m not a videographer or burst shooter.

  2. blank

    Hi guys — thanks for these results — but since 2.0 was adopted many cards have been updated and are now faster and cooler AND many new entrants have release products. Would you guys consider repeating these tests – might I recommend the new 650GB Delkin Black, the Sabrent Rocket XXIT-2TB, and the Angelbird AV Pro 2.0 – 2TB and 4TB

Leave a Reply

Your email address will not be published. Required fields are marked *