I have a setup very similar to yours. 2010 Mac Pro 6-Core, CalDigit FASTA-6GU3 PCIe card, and Lexar USB 3.0 Dual Slot card reader.
I see the same speed specs in System Profiler -- the 480Mbit/sec rating for the USB 3.0 card reader. In practice, I'm not sure it's accurate.
Mark
Thanks so much for your response. Let me update as to what I have found out after much more research--
1) Since my previous Post I finally
received a detailed and informative response from CalDigit which I will include for the benefit of others, since it really helped me out as well. The following certainly explains the variables that influence the performance of the Lexar USB 3.0 Dual Slot CF Card Reader as well as what one needs in order to achieve the Read/Write Speeds that the USB 3.0 interface offers.
_________________________________________________
FROM CALDIGIT SUPPORT:
Dear customer,
"Here're some backgrounds:
1. CalDigit USB3.0 card
- It looks like our driver and bandwidth requirements are fulfilled, so the card is running properly.
2. CF card
- CF card plays a very important role in this application.
- For example: we are using the Lexar Professional 600x 16GB CF card, and it's able to hit over 80MB/s on the Lexar USB 3.0 DualSlot CF Card
Reader (high 70MB/s via the Delkim Card Reader).
- Lexar and Delkim are the only two USB3.0 card readers that we certified.
3. 5.0Gb/s vs. 480Mb/s vs. Firewire 800 (Mb megabit per second, MB is megabyte)
- 5.0Gb/s is the capped bandwidth for USB 3.0, which means the USB 3.0 rough output is capped around 400MB/s.
(
http://en.wikipedia.org/wiki/USB_3.0#Data_encoding)
- 480Mb/s is the capped bandwidth for USB 2.0, which means the USB 2.0 rough output is capped around 35MB/s.
(
http://en.wikipedia.org/wiki/Universal_Serial_Bus#USB_2.0)
- For Firewire 800, the capped speed is around 70~85MB/s
4. Can any current CF card capped USB 3.0 bandwidth (hitting over 400MB/s)
- No, one of the fastest CF card can only reach 150MB/s (
http://www.lexar.com/products/lexar-professional-1000x-compactflash-card).
5. 480Mb/sec in system profile
- In system profile, it will never show the 5.0Gb/s. This is due to the lack of SuperSpeed USB profile, which the OSX have to category any USB 2.0
and USB 3.0 with their fastest USB profile (which is 480Mb/s). This means the OSX does not have the 'name' for the USB 3.0, so they can
only brand the USB 3.0 connection with the 'wrong name'.
- For example: eSATA is widely recognized connection, but it was never officially adopted by Mac. In the Disk Utility, any eSATA drive will show up
as "external SCSI" (wrong name because lack of profile). Keep in mind, the wrong 'profile' name will not affect the actual output of the connection.
Here're some of the possible causes:
The CF card is not fast enough to show any difference.
- For example: our Lexar Professional 600x card is able to perform around 80MB/s. If we compare the test results between USB 3.0 and USB 2.0
(80MB/s vs 35MB/s), the performance difference is very signifacnt. However, if we compare the test results between USB 3.0 and Firewire 800
(80MB/s vs 80MB/s), the results will be very similar.
- If we used one of the slower card, which its performance is only about 35~40MB/s. Its performance results will be identical between USB 3.0,
USB 2.0, and Firewire 800 (because the card isn't fast enough).
Here's our suggested test:
1. Find the spec of your CF card
- knowing how fast the card is suppose to perform.
- For example: the Lexar 600x's web site said 90MB/s, but the real world performance is about 80MB/s (still within a reasonable range)
2. Run a simple speed test
- make sure the card is not 'too full' already
- Run an AJA System Test to check the speed. http://www.aja.com/ajashare/AJASystemTest.zip >>> 1920x1080 10bit RGB / 512MB test size /
Others settings: default
Please remember:
If your CF card is not faster than 40MB/s, the USB 3.0 card reader is pointless.
If your CF card is about 60~80 MB/s, the USB3.0 card reader should have to same result as your Firewire card reader (both are faster than the USB
2.0 connection).
If your CF card is about 100MB/s+, the USB3.0 card reader should be faster than the Firewire card reader.
Also, as long as the USB 3.0's performance is higher than 40MB/s, our card is running with the USB3.0 speed. (There's no way for an USB2.0
connection to exceed 40MB/s)."
BEST REGARDS: CALDIGIT SUPPORT
_____________________________________________
ME AGAIN!: Since I was initially using the Lexar Professional 300X CF Card the testing resulted in 32-35MB/s Downloads(similar to USB 2.0, but I guess that's all that can be expected on a 300X Card). After receiving a new 16GB Professional 600X CF Card and testing it I was receiving 64-66MB/s Write & 83-84MB/s Read.
Now CalDigit States that they are receiving Speeds of 80MB/s from the Lexar 600X Card using the Lexar USB 3.0 Dual Slot CF Card Reader. My question on this - What data results are they referring to? Read Speed or Write Speed? As you can see by my results the difference between the two speeds, although I am receiving over 80MB/s Read I am only around 65MB/s Write? When I'm downloading my Raw Images from the Lexar Card Reader to My Hard Drive I would assume that the Process is to Read the data from the Card then Write the Data to the Hard Drive. So that is a two stage process, so is CalDigit just picking which ever sped is fastest?
Bottom line is--I am getting much better speeds with the Lexar 600x Card than I was with my Lexar 300x Card, which saves me some time, which I like!
Thanks to all who responded at MacRumors, much appreciated! I hope the above from CalDigit may help others like myself!
