In running an OS, solid state storage (whether it’s an SSD or SD card) also has an advantage in non-sequential data access speed, compared to a hard drive. Running an OS is more about reading data, not writing data (unless the task being performed at the moment is writing data). In my testing, reading data FROM the SD card is about three times faster. It is likely that you did your testing by writing a large amount of data TO the SD card. My Mac mini, which is actually not that new (released in 2011), has a high speed SD card slot.Īlso, there is a significant difference in speed between reading and writing. Therefore, the bottleneck may be the Mac’s interface, not the SDXC card. The “high-speed” SD card slots on more recent Macs are faster. SD card slots on older Macs are slower I believe they use the USB bus.

Since I don’t use my SD card slot (on back of my Mac mini) for anything else, I just leave it in there. It becomes a super- “Recovery HD” for maintenance and emergency boot. Provides accurate user experience for testing the beta.Īfter beta testing is over, you can put a standard install on it, along with any third-party disk utilities (like TechTool Pro) you may have. Faster than booting from USB (2.0) or FireWire. Not as fast as an internal SSD, but on par with an internal hard drive. Run the OS X installer and select it as the target just like any volume. Use Mac OS Extended (Journaled) as Format. Click Options button and select GUID Partition Table. Re-initialize it for Mac using Partition tab in Disk Utility.

32GB gets a bit tight on space, if you want to test throughly. I’ve recently seen 64GB SDXC cards for about $30. If your Mac has a high-speed SD card slot, like my Mac mini, a better solution is to use an SDXC card that is at least 32GB.

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