I concur,
There has been a lot of whining over this issue. Now USB 3.0 drivers for Mac are out. It is a very good development that should satisfy the vast majority of users. If you are using a 5+ year old laptop with discontinued tech (the expresscard slot) you can hardly expect new products developed for you. It would be more beneficial on many levels if you updated to a newer mac. IF you thought you would be able to use the USB 2.0 ports on your mac, that is a very poorly technically informed idea. IF you thought you would be able to use the product with an expresscard to usb 3.0 adapter, that may actually work. If not now, eventually. I suggest you research a driver called GenericUSBXHCI.kext. It works quite well for a grass roots driver and is well regarded for storage devices. It has enabled the Isochronous Endpoints provisions needed to technically use a blackmagic device, but there can be no guarantee it will work well, or at all.
You can try one of the many expresscards based on the NEC/Renesas chipset, or this one based on asmedia may work better:
http://www.ebay.com/itm/New-2-Port-USB- ... vi-contentIt may take some testing to see which chipset works best with the driver and intensity, and chipset options in the expresscard for factor seem pretty limited.
You would have to test it. That's the life of someone who wants to hack together tech to work on very old equipment.
As one more alternative, albeit a very expensive one, you should be able to use a magma expresscard to PCIe chassis and one of the PCIe based blackmagic devices.
I just don't see how the burden here falls on blackmagic or that there is even anything they can do about the issue. Rather it's time for an upgrade.
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