RAM still faster than flash memory

With all the trumpets and fanfare over nonvolatile flash memory getting cheaper as chip capacities rise and use of the product widens, remember that as a replacement for traditional electronic components, results may vary.

Simply put, when flash replaces a hard drive, access times could very well improve. But when flash replaces traditional random access memory, be prepared for a slowdown.

One of the novel features of the new Windows Vista is the ability to add to available system RAM by plugging in a flash drive. Not a bad idea, since Vista reportedly needs 2 GB of RAM to be comfortable. But as early Vista users are learning, only the newest, fastest flash cards and drives will even work at all.

New and recent Palm handhelds illustrates this point well. The newish LifeDrive, which deviates from traditional Palm devices in that it is built around a 4 GB hard drlve (hence the name -- LifeDRIVE), is markedly slower to start applications than other Palms. Once started, the apps stay in RAM, so speed improves, but the LifeDrive does appear quite sluggish in comparison to its cheaper Palm cousins.

The Palm TX and Tungsten E2 models are the company's first handhelds to use flash memory instead of battery-backed RAM. I was surprised that both handhelds were slower to start applications than my older Tungsten E with its 32 MB of traditional RAM.

The tradeoff: The Palms with flash memory enjoy increased battery life, and you'll never lose the content of your Palm to a dead battery. However, users of older Palms say that even a handheld that won't power on will retain its data in RAM for some time and can still be backed up with a HotSync if it's done in a somewhat timely manner.

Still, the speed differential between more modern flash and RAM is not a total deal-breaker in some devices, but for now, flash is a better substitute for disk-drive-like storage than it is for heavily accessed system memory.

To further complicate it all, some flash is slower than the average hard disk. And since disk speed is typically measured in milliseconds of access time, while flash memory is measured in megabytes transferred per second, nothing is easy.