Thursday, July 29, 2010

solid state drive vs hard drive


Solid-state disk (SSD) drives are all the rage among techies. The drives use non-volatile NAND flash memory, meaning there are no moving parts. Because there is no actuator arm and read/write head that must seek out data on a platter like on a hard disk drive (HDD), they are faster in reading and, in most cases, writing data.
With the very fast paced lifestyle these days, most businesses are time-bound and cannot afford a slowing down in their transactions. This makes speed of HDDs a crucial point in technological purchases. The typical access time for a Flash based SSD is about 35 - 100 micro-seconds, whereas that of a rotating disk is around 5,000 - 10,000 micro-seconds. That makes a Flash-based SSD approximately 100 times faster than a rotating disk. 
This however raises another point - what's the benefit of a high-speed SSD when the entire system cannot support it? The evolution of CPUs in terms of performance has far surpassed the development of the data storage system. The HDD is actually limiting the potential of a computer system when they are not able to keep up with the performance of the other components, particularly the CPU. If an HDD is replaced by a high-speed SSD, the performance would significantly improve. The resulting system would be a high-powered set-up that can go beyond the demands of high-speed business or military environments. 
In terms of reliability, conventional HDDs pale when compared to SSDs. The absence of mechanical arms and spinning platters is the reason behind its reliability. In demanding environments, SSDs provide the type of ruggedness required for mobile applications. Unlike the HDD, SSD's can withstand extreme shock and vibration with data integrity and without any danger of data loss. This feature is very important in industrial applications where exposure to highly combustible materials and electromagnetic radiation are typical. Their ability to deliver unnerving performance in extreme conditions also makes SSD play a vital role in military operations, be it in defense, aerospace or aviation applications. Military applications require, in most cases, an operating temperature range of -60°C to +95°C. Shock, vibration, and temperature ratings of HDDs cannot comply with military standards, only SSDs can. 
But SSDs are also much more expensive than their hard-disk drive (HDD) counterparts, which offer 300GB of capacity or more for less than $100.
Most consumer-grade SSDs from leading vendors now cost around $3 per gigabyte, while traditional hard drives cost about 20 to 30 cents per gigabyte for 2.5-in. laptop drives and 10 to 20 cents per gigabyte for 3.5-in. desktop drives. In other words, even the cheapest 120GB SSDs are going to be around $300, though some are available on sale for less. So should you buy a high-capacity HDD for little cash or plunk down hundreds of dollars more for a fast, but lower-capacity, SSD? Or, should you wait?


networld