Announced earlier this year, Lexar is preparing to ship their Professional UDMA Dual-Slot USB Reader next month. Lexar's newest USB 2.0 memory card reader is the first we know of to combine support for the higher speed of UDMA-capable CompactFlash cards and the ability to accept SD/SDHC cards with performance that's in line with the fastest USB 2.0 readers currently available. In our benchmarking of a preproduction unit, it's as quick in card-to-computer transfers as any USB 2.0 CompactFlash reader we've seen, and the fastest SD/SDHC reader we've ever tested.
Lexar's Professional UDMA Dual-Slot USB Reader is comprised of twin memory card slots - one for CompactFlash (Type I and II), the other for SD/SDHC - and features a silky smooth pop-up, pop-down mechanism meant to protect the slot openings when the reader is not in use. On the back of the reader is a single USB mini-B port; the reader will ship with a USB mini-B to A cable. On the base of the reader is a non-slip pad that keeps it from moving about the desk. Though the semi-translucent design of the unit's lower half gives it a somewhat dated appearance, the overall industrial design of this reader is quite nice.
Double Down: Views of the Lexar Professional UDMA Dual-Slot USB Reader. Click any photo to enlarge (Photos by Rob Galbraith/Little Guy Media)
Under the hood, the Professional UDMA Dual-Slot USB Reader supports both the UDMA (up to Mode 4) and PIO (up to Mode 6) CompactFlash data timing protocols, and also accepts both SD and SDHC.
As a CompactFlash reader, it keeps pace with the CompuApps OmniFlash USB 2.0 UDMA 40 UnoCF
, which is the speediest UDMA-capable USB 2.0 model we've tested. When copying about 450MB of Canon EOS-1D Mark II N JPEGs and CR2s from today's fastest UDMA CompactFlash to the computer, transfer rates top out at just over 26MB/second to our Windows XP SP2 custom-built desktop machine. This drops to about 23MB/second in Windows Vista on the same computer, and to just over 20MB/second with an Apple Mac Pro desktop running OS X 10.4.10.
Transfer rates top out at almost 19MB/second with quicker SDHC cards, and a little under 18MB/second for SD, in Windows XP SP 2 (we didn't test this reader with SD/SDHC cards in Vista). This makes the Professional UDMA Dual-Slot USB Reader the quickest SD/SDHC reader we've used, though by a small margin. If you're looking for maximum throughput from SD/SDHC memory cards, Lexar's new reader is it.
The CompactFlash throughput numbers, while respectable, fall short of what's possible when you combine a UDMA-capable card, a reader like the SanDisk Extreme Firewire
(or any other modern FireWire 800 reader that uses a chipset from Oxford Semiconductor) and Windows Vista. Transfer rates above 32MB/second are possible with cards from several different makers, including Delkin, Lexar, SanDisk and Transcend. Do the same test with a Mac and those numbers climb above 38MB/second, with some cards capable of more than 42MB/second. In Windows XP, the gap is much smaller; our testing shows a real-world top speed of about 28MB/second for the fastest UDMA cards and FireWire readers.
The Professional UDMA Dual-Slot USB Reader matches the performance of the fastest USB 2.0 CompactFlash reader we know of, and is the quickest SD/SDHC card reader we've tested. If you're looking for a USB 2.0 reader that will support these memory card types and deliver overall speedy throughput, Lexar's new offering is a fine choice.
If, however, you need the fastest possible throughput from UDMA CompactFlash, and you're on a Mac especially, a recent-vintage FireWire reader is the better way to go. We're partial to the simple design and great speed of the SanDisk Extreme FireWire Reader, but the same speed is available in Lexar's Professional UDMA FireWire 800 Reader
(they share the same chipset) and a handful of other FireWire 800 readers on the market too.