Memory Cards as Solid State Drives

Often when we think of memory cards, we think of cameras.  However, their utility extends beyond cameras.  Most memory cards are based on standard computer protocols meaning that they can be used to replace spinning hard disk drives in computing systems.  How?  With the addition of the appropriate adapter.  Let’s examine 4 different memory card types and weigh up the pros and cons of using them as Solid State Drives (SSDs).

CompactFlash

A popular memory card format based on the IDE/ATA/PATA standard.

PRO: Great in older systems that require IDE protocol. Relatively cheap ($3.8/Gb)

CON: Limited to 133Mb/s

CFast

CFA’s first attempt at improving the CompactFlash standard, CFast has the same form factor as CF, but based on the SATA standard.

PRO: Faster than CompactFlash and SDHC (300Mb/s)

CON: Very Expensive ($16/Gb)

SD/SDHC/SDXC

Perhaps the most ubiquitous of all memory card formats, small and found in almost all electronic store, they are cheap and readily available.

PRO: Cheap ($2/Gb) and readily available.

CON: Slow, small size, easy to lose. SD/SDHC was not originally intended to be used as ATA storage.

XQD

CFA’s latest creation, XQD is based on the PCI Express standard.  Sony are the first to announce the first commericially available XQD card and ExpressCard adapter.

PRO: Very fast (500 Mb/s)

CON: Expensive ($8/Gb), new and not yet reached critical mass.  Major memory card producers Sandisk, Lexar, and Kingston have no plans to produce XQD cards, leaving the future of the format in doubt.

Conclusion

I have used CompactFlash as a solid state drive in my Macintosh SE/30, with appropriate adapters, I have also used SD and SDHC cards successfully.  CFast and XQD are newer technologies that may supplant CF and SD in the future, but at the moment they are simply too expensive and too green to adopt at the moment, nobody wants to be stuck with with redundant technology (think Betamax and HD-DVD).