NWA-PCUG Newsletter Article, May 2012
“Driving” Your Computer
By Diane Fahlbusch,
President, ICON PC User Group, NY
http://www.iconpcug.org
Editor (at) iconpcug.org (click to email author)

We all know that one of the most essential components of our computer is the storage drive. It is the home of your operating system, firmware, applications and those precious files you have collected over time. Faster processors, more RAM … are useless if there is nothing to pass through them. We now have tremendous options available to us: larger capacity, faster RPMs, newer materials, faster connections, external drives and thumb/flash drives. The more you know about them, the better you will be able to decide what is right for you.

Floppy Drives
Yes they still do exist! But they have almost waved themselves goodbye. In their day they were great, and became smaller. But as the capability of computers increased and technology advanced, they just did not have the capacity, were too bulky and very fragile little things. But, they are still designated as the A drive, and the standard “Save” icon.

Zip Drives and Jazz Drives
Yes, they still do exist! These were inherently floppy drives on steroids to meet larger capacity demands, as well as being able to function faster. But these are also stored to a magnetic film, which will erode over time, and are subject to semi-severe conditions. So if you still have anything you want from these, it is recommended that you transfer your data to a newer format.

CD Rom Drives
These sounded the beginning of the end for floppy drives and their kin, as well as cassette tapes and vinyl records. Writable CDs are very inexpensive now, and consist of various layers. The top layer is actually a protective coating, which is why scratches to this layer may be able to be repaired with Skip Disc, or something similar. The data is stored on a different layer. There are plenty of these drives still around, and it’s not a bad idea to slap one into your tower unit if you have room. This way you can burn out the CD only drive and save the:

CD/DVD Drive
This is the dual drive that is now standard on any computer, and very similar in physical design to CDs. If you need to replace one, watch for read and write speeds, which are far faster than the ones just 5-7 years ago, as well as any firmware updates you might need for faster write speeds to work. Do not forget to watch the read/write speeds of the discs you buy, as well as whether your drive can burn +R DVDs. Also watch for the “new” thing from just a few years ago, dual layer. But of course the latest is:

Blue Ray Drive
An essential for REALLY large capacity discs or to watch blue-ray discs with high definition graphics. Of course, if your monitor is not high definition or your computer’s video card does not know what to do with HD files, you may just want to wait on this one. It’s still very pricey – even the stand-alone units to connect to your HD TV.

Hard Disc Drives
The vast majority of storage drives available are still the good ol’ magnetic discs. The original design of the rotating, rigid platters storing data magnetically by read/write heads floating on a layer of pressurized air is still the same as it was from the 1960’s, but the recording density has increased dramatically. The platters themselves are not made of a magnetic material. They are coated with a thin layer of magnetized material, which has changed over the years. The platters are held together on a spindle, which requires very careful placement to allow for just enough air between each platter as well as the read/write heads.

Disc drives also contain two electronic motors. One motor spins the platters at a specified RPM. The faster the RPM, the faster the drive can access the data - and the greater the heat output. The platters do have a special coating to resist thermal-induced magnetic breakdown, but it is still very important to make sure that your cooling fans are working properly, and more important to check or change your fans if you replace the factory installed drive with one with a faster RPM. The second is called an actuator motor to control the read/write heads. If they no longer line up correctly, they will not function properly. It is possible to reset the placement of the heads if they are no longer lining up properly – but not easy. Of course, if your drive has experienced a “Head Crash”, where the misplaced head has actually scraped along the surface of the disc, those sections are destroyed forever.

Your data is stored in digital magnetic format on the platters on disc drives. Once a brand new hard disc drive has collected any information, it will never be the same as it was in its pristine state – just as a magnet will always have some residual iron filings no matter how hard you try to remove them. And of course another way to help prevent the loss of the data is for the correct magnetization to be stored with some room to spare. But that concept of “elbow room” shrinks as there is more data stored. One way to think about this is by comparing the way some neighborhoods look today versus 25 years ago. (The Smithhaven Mall used to loom out of nothingness like Oz’s Emerald City – now you can miss it because there are at least three other shopping centers/malls around it.) So if your data was originally being stored with plenty of space, you will wind up with fragmented files as that space shrinks. Defragmenting your hard disc drive is one of those easy maintenance things to do to speed up performance, because it moves related pieces of information near one another for faster access. However, you can rewrite to a hard disc drive as long as the device is working properly. Of course, there might be residual bits of magnetic charges left on that previously written space which might corrupt your file.

Hard disc drives seem sturdy because of their tough protective casings and hard materials, but they are not made to withstand sudden shock, such as being banged or dropped, especially when still spinning. Some notebook computers now come with an active hard drive protection that parks the disc heads if the unit is dropped. Hard disc drives are also sensitive to power surges (including static electricity), sudden loss of power, contamination within the enclosure, corrosion and exposure to excessive heat or magnetic fields. Some recent studies seem to show that disc drives maintained at somewhat colder temperatures do NOT outlast those at somewhat warmer ones, as previously believed. All drives will experience normal “wear and tear”. Interestingly, your disc drives are like your car – it’s better for the engine if you take longer trips instead of the short hops, or leaving it idling. One way to reduce the life of your drive is by leaving the computer on, but in an idle state. It is better to shut the computer off when you are not using it. Of course, excessive rebooting will also shorten the life of your disc drives, as they have to spin up every time.

Solid State Drives
The newest data storage drive is the solid state drive, which is radically different than its predecessor. These drives use microchips to store the data to free, programmable blocks and do NOT contain any moving parts. Because of this they are quiet, physically smaller, use less power to operate, run cooler, can tolerate greater altitudes and temperature ranges, tolerate vibration, are not susceptible to magnetic fields, do NOT require defragmenting (actually, defragmenting adds wear for no benefit) and are less susceptible to sudden shock. (But that does NOT mean that you should be playing handball with them!) Performance is most frequently tied to the type of memory used and the controller, an embedded processor that works as a bridge between the computer’s electronics and its own, as well as a number of other factors. They will typically use either non-volatile (NAND flash) memory or volatile (DRAM) memory.

The NAND flash based memory, while being slower than its counterpart, has an advantage – it can retain information WITHOUT power. That is why your camera cards and thumb/flash drives do not need a separate power supply. This memory can be MLC (multi-level cell), or single-level cell, the latter of which is more reliable and faster, but more expensive. Also, the NAND flash memory cannot directly overwrite a file. It must first rewrite the information to free programmable blocks of space, THEN it overwrites the previous blocks. If data was encrypted with an encryption program NOT located on the drive itself, the original data, can only be safely “wiped” by using a special “secure erase” program on the drive. Effectively, this means that your once secured information is unsecure, unencrypted and accessible. And these blocks do have a limit of 1,000,000 to 2,000,000 write cycles (1,000 to 10,000 per cell) for MLC, and up to 5,000,000 write cycles (100,000 per cell) for SLC. This is compensated for by “wear leveling” – writing to different sets of blocks each time and spreading the usage out evenly. (Think of it as a little league coach who always rotates all of the players in every game, but does a quick tidy-up at the end of the game.) This effectively means that you will eventually “use up” the memory. When that happens the drive just stops working. Granted, it may take a many years, but it depends upon how much you create, or re-create.

The DRAM provides lightening fast data transfer, and does NOT have a limit to the number of times programmable blocks can be written to. It also requires an internal battery or capacitor or other power supply, and requires backup storage systems to ensure preserving data if power is lost. These are most frequently used as internal drives in netbooks and computers. Because nothing needs to spin during boot up or starting up applications, these drives respond rapidly. Their read times are far less than hard disc drives, again because there are no heads to search for the data. However, these drives do have certain drawbacks.

For starters, solid state drives with DRAM are far more expensive, but the price is coming down. Because of this, there really are not many large capacity solid state drives available. Be wary that there are some of these drives are using a combination of NAND and DRAM. Another consideration is the write speed. Less expensive models may not be providing much faster write performance than hard disc drives, but will be impacted significantly by the number of free programmable blocks. Solid state drives are really not the best choice for operating systems that continually rewrite to the drives while in use, such as Windows. While solid state drives CAN provide greater performance, be aware that you can only push the information through as fast as your connection can handle. Having a USB3 device will not increase the speed of data transfer if your computer’s connection is USB1. Write performance is greatly reduced when using a SATA connection. Performance of DRAM drives will deteriorate in time when there are no free programmable blocks left. Also, as previously mentioned, DRAM requires constant power. So even though your computer is turned off, the DRAM drive still requires power.

Please always remember to make educated decisions about the products you select, and set realistic expectations on any hardware you use.

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