ProGrade Digital Cobalt CFexpress 2.0 Type B Tested

The Cobalt series is ProGrade Digital’s flagship memory card lineup. It offers the fastest maximum read and write speeds and sustained write speeds that eclipse its Gold and Iridium lineups. In this review, we’ll be discussing the CFexpress 2.0 Type B Cobalt cards. The CFexpress 2.0 Cobalt Type A cards were reviewed separately for Sony users. Long-term in-camera testing was performed in the Canon R5, Nikon Z9, and Z8, and I traveled worldwide for my photography. Once satisfied with overall reliability and durability, I performed my usual controlled speed tests to compare the card to others on the market, and form a final conclusion.

Disclaimer: ProGrade Digital provided the Cobalt CFexpress card for testing. No money changed hands, and they were not allowed to see the content before it was published.

ProGrade Cobalt CFexpress 2.0 Type B Specifications

• Card Type – CFexpress Type B
• Card Specification – CFexpress 2.0
• Maximum Read Speed – 1700 MB/s
• Maximum Write Speed – 1500 MB/s
• Minimum Write Speed – 1400MB/s
• VPG Rating – No
• Capacity – 165GB, 325GB, 650GB
• RED Approved – Yes
• Operating Temperature – 14 to 158°F / -10 to 70°C
• Storage Temperature – 4 to 185°F / -20 to 85°C
• Dimensions – 29.6mm x 38.5mm x 3.8mm
• Price – $179.99-$999.99 at review time – Check the current price

ProGrade Cobalt CFexpress 2.0 Type B Speed Testing

This card’s speed testing was performed using the ProGrade Digital Type B USB4 card reader. Note that if you use a USB 3.2 reader, your card speeds will be slower, and your download times will be longer. I have written about how CFexpress 2.0 cards can still benefit from being used in a CFexpress 4.0 reader.

For reference, ProGrade Digital says these cards should reach 1700MB/s in maximum read speeds and 1500MB/s in maximum write speeds. The write speed shouldn’t drop below 1400MB/s in longer large file writes.

Test Result Discussion – Good or Bad?

The ProGrade Digital Cobalt CFexpreess Type B is one of the fastest cards on the market. Although I didn’t quite reach the claimed maximum read and write speeds, I came very close. These maximum speeds are the second fastest I have ever recorded, just behind the Lexar Diamond Type B card.

While card manufacturers like to tout maximum read and write speeds, they don’t tell the whole story. The card performance metric that makes the most difference to many people is sustained write speeds. In this test, the Cobalt 325GB card yielded the best result I have ever seen for a CFexpress 2.0 card. ProGrade says the minimum sustained speed is 1400MB/s, and while I measured it slightly slower than that on the very large file writes, it was still faster than my results for the highly acclaimed Lexar Diamond card.

Alternative CFexpress Type B Cards

Type B 4.0

Type B 2.0

Conclusion

The ProGrade Digital Cobalt CFexpress 2.0 Type B card is among the fastest 2.0 specification cards on the market. Whenever a card has a sustained write speed that is so close to the maximum write speed, you know you’re looking at a high-end memory card, and in this regard, the ProGrade Cobalt doesn’t disappoint with real-world sustained writes just shy of 1400MB/s.

The problem is that from 2024 onwards, CFexpress 4.0 cards hit higher maximum read and write speeds than this slightly older 2.0 card. While the Cobalt card in its CFexpress 2.0 guise still turns in respectable sustained write speeds, it is beaten by the Cobalt 4.0 card with its claimed 2100MB/s sustained speed. However, that card is only available in a 1.3TB capacity, costing $999.

On the other hand, ProGrade’s Gold 4.0 card claims to reach 1300MB/s for sustained writes and costs just $349.99, compared to $539.99 for the 650GB Cobalt 2.0 card. For a like-for-like capacity comparison, compare the OWC Atlas Ultra 4.0 card with its 650GB capacity for $249.99–less than half the price of the 650GB ProGrade Cobalt 2.0 card, while offering significantly faster download speeds and a faster 1500MB/s sustained speed test result in my tests. When it was first launched, this ProGrade Cobalt 2.0 card was an exceptional performer, but I have to say, at this point, the only reason to buy this card would be if it was on sale for a significant discount.