SandForce SF-1200: Does Lower Capacity Mean Lower Performance?
 

Up until now we have observed SSD manufacturers quoting different performance numbers for each capacity size in a product line. The most obvious came in 2009 when some manufacturers listed as many as four distinct performance envelopes in their Indilinx Barefoot products with all divided by capacity. The Indilinx Barefoot products weren’t the only ones listing footnotes about performance, Intel had a few of their own as well.

There are many reasons why smaller capacity drives can be generally slower than higher capacity drives. Without boring you with technical details, we will just briefly touch on technical side. The first possible reason a smaller drive performs less than a higher capacity drive can be linked directly to the flash memory itself. Some smaller drives use smaller flash memory that does not perform as well as larger capacity flash. The next issue and what we saw mostly in 2009 and early 2010 were smaller than 128GB drives that were using less of the available channels on the controller.

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