CARDSPEED - Card Readers and Memory Cards

UDMA CompactFlash Cards

 Market Overview   ·   CARDSPEED Tests   ·   Explanations 

Market Overview

This is a list of currently available or announced UDMA CF cards.

Last update: 2008-04-30 Sizes
Brand Series Claimed Speed  1GB   2GB   4GB   8GB  12GB 16GB 24GB 32GB 48GB
A-Data Turbo 266x CompactFlash 266x   # # #   [#]      
Apacer Photo Steno IV CF 300X 300x - 47MB/s Read, 36MB/s Write     # #   [#]      
ATP Pro Max II UDMA Ready 300X Speed CF 300x   # # #          
Buffalo RCF-U x300 45MB/s Read, 35MB/s Write     # #          
Calumet ProSpec Series UDMA 305x 305x - 45MB/s # # # #   #      
Delkin CompactFlash PRO UDMA 305x 305x - 45MB/s # # # #   #      
Hoodman Professional RAW 280x CompactFlash 280x - 42MB/s   # # #   [#]      
Kingston CompactFlash Ultimate 266x 266x - 45MB/s Read, 40MB/s Write   # # #          
Lexar Professional UDMA 300x CompactFlash 300x   # # #          
Microdia XTRA Elite 300x UDMA CompactFlash 300x - 45MB/s Read/Write     # #   [#]   [#]  
PNY Optima Pro UDMA CF Ultra High Speed 266x 266x   # # #          
PQI Hi-Speed 300 CompactFlash 300x - 45MB/s Read, 22.5MB/s Write # # # #   [#]      
Pretec 333x 333x           [#] [#]    
Pretec 233x 233x                 [#]
RiDATA 266X CompactFlash Supreme 266x - 40MB/s Read, 35MB/s Write # # # #          
RiDATA Lightning Series 233X CompactFlash 233x - 35MB/s Read # # # #   #      
SanDisk Extreme IV CF 266x   # # #          
SanDisk Extreme Ducati Edition CF 45MB/s     # #          
Silicon Power 300x CF 300x   # # #          
SONY CompactFlash UDMA 300x 300x - 45MB/s Write   # # #          
STEC MACH4 CF 90MB/s Read, 55MB/s Write     # #   #      
STEC MACH2 CF 30MB/s Read, 20MB/s Write # # # #   #      
Transcend ULTRA Industrial CF 100x - 25-40MB/s Max. # # # #          
Transcend Extreme Speed UDMA 300x CF 300x     # #   #      
Transcend 266x High-Speed CF 266x - 40MB/s Max.   # # #          
Transcend 133x Ultra Speed CF 133x - 45MB/s Read, 21.5MB/s Write # # # #   #   #  
TwinMOS 300x Ultra-X CF 300x # # # #   [#]      
Verbatim PRO SERIES CF 300X 300x - 45MB/s Read/Write   # # #          

CARDSPEED Tests

   Read   Write   Max. Mode   ATA Type
 Transcend UDMA 300x CF 16GB  51.34MB/s 350x 49.70MB/s 339x UDMA-5 Fixed + CF-Removable
 SONY 300x UDMA CF 8GB  43.11MB/s 294x 46.30MB/s 316x UDMA-5 CF-Removable
 Lexar Professional UDMA 300x CF 8GB  41.82MB/s 285x 44.99MB/s 307x UDMA-5 CF-Removable
 SanDisk Extreme Ducati Edition CF 8GB  43.00MB/s 293x 43.65MB/s 298x UDMA-4 CF-Removable
 SanDisk Extreme IV CF 4GB  40.08MB/s 273x 38.97MB/s 266x UDMA-4 CF-Removable
 Kingston Ultimate 266x CF 8GB  44.12MB/s 301x 38.74MB/s 264x UDMA-5 Fixed + CF-Removable
 Transcend 266x High-Speed CF 8GB  45.26MB/s 309x 36.60MB/s 249x UDMA-4 Fixed + CF-Removable
 Transcend ULTRA Industrial CF 8GB  42.90MB/s 282x 35.69MB/s 243x UDMA-4 Fixed + Standard
 A-Data Turbo 266x CF 8GB  47.66MB/s 325x 29.29MB/s 200x UDMA-4 Fixed + CF-Removable
 TwinMOS Ultra-X CF 300X 4GB  28.01MB/s 191x 21.54MB/s 147x UDMA-4 Fixed + CF-Non-Standard
 Transcend 133x Ultra Speed CF 16GB  34.26MB/s 233x 15.26MB/s 104x UDMA-4 Fixed + CF-Removable

Explanations

What's the big deal with these UDMA CF Cards? The CF interface is derived from the ATA interface. The CF 2.0 specification allowed PIO-4 mode that has a theoretical limit of about 15.9MB/s. CF 3.0 introduced two additional PIO modes that are not part of the original ATA specification: PIO-5 and PIO-6, where PIO-6 has a theoretical limit of about 23.8MB/s. Most CF cards with speed ratings from 80x to 166x use PIO-6 to achieve this speed. However, there is currently no FireWire reader with support for PIO-6. This means that PIO-6 cards run in the slower PIO-4 mode, and therefore run slower than with current USB 2.0 readers. Support for MDMA modes is most likely not that popular, but you can't really tell the difference between PIO-4 and MDMA-2 when a card reader is used, because PIO only occupies the card reader controller, not the host CPU.

With CF 3.0, the UDMA modes UDMA-0 to UDMA-4 were introduced with a theoretical limit of about 63MB/s for UDMA-4. With CF 4.0, the remaining UDMA modes UDMA-5 and UDMA-6 were added, allowing up to about 127MB/s.

Current UDMA CF Cards and UDMA CF readers support UDMA-4 with real-world transfer rates of almost 49MB/s. This is already well beyond the real-world throughput of USB 2.0 in storage mode. Current USB 2.0 UDMA CF readers are maxed out at about 32MB/s.

Hans-Jürgen Reggel   ·   http://www.hjreggel.net/cardspeed/   ·   2007-05-21 ~ 2008-05-07