Debunking USB Flash Drives: Comparing Cost, Performance

Infopackets Reader Brad B. Writes:

" Dear Dennis,

Regarding USB flash drives: how do I know which USB thumb drive is a good one? I bought a 4 gig flash drive that is incredibly slow, and another that is much faster. They both say they are USB 2.0 and cost about the same price. So how can one know which to buy? "

My Response:

There are a few things to consider here.

Regarding USB specifications: USB is simply an interface. If a product says it's USB 2.0 compliant, that doesn't necessarily mean it will operate at full USB 2.0 speeds.

What determines the speed is the memory chip inside which stores the data. The same rule can apply to harddrives. SATA is an interface that can do up to 3 GBits/second (not gigaBYTES), but most harddrives are considerably slower (at around 150 megabytes/second). Source: (wikipedia.org)

USB Flash Drive: Rules of Thumb

There are a few "rules of thumb" (no pun intended) that you can use when deciding on which thumb / flash drive to buy.

a) Cheaper flash drives typically use slower memory.

b) Better brand name drives typically use faster memory, but not always.

c) Pay attention to descriptions like "150x transfer speeds", and -- even better -- look for details regarding read and write speeds. Typically read speeds are faster than write speeds.

d) The bigger the storage size of the USB drive, the faster it is in read / write speeds (typically).

e) To compare speeds relative to price / performance, look and see what others are saying about certain units before you make your purchase.

Hope that helps.