Question: I would like to see an article on hard drives – speed, size, transfer rates, buffers, etc. I find it hard to figure out which is faster. The size I’m considering is 1.6 to 2.5 gigs. —G.Y.
Answer: Of all the components on a computer these days, a hard drive replacement or addition is one of the easiest to explain. My first tip is this: Buy big. Hard drives are like landfill sites. They always look huge, but they fill up faster than you expect. So buy the biggest drive you can afford.
My first machine was an XT and it came with a whopping 20-meg hard drive. It was huge. Now I have two 1.2 Gig hard drives on my home machine and it is nearing capacity.
When shopping for hard drives, the big consideration is to choose between an E-IDE or SCSI hard drive on the PC side. (On the Mac side your Performa will come with an IDE drive. The faster Macs come with a SCSI drive.)
First some definitions. IDE stands for “Intelligent Drive Electronics” or
“Integrated Drive Electronics”, depending on who you’re talking to. E-IDE is simply an Enhanced IDE drive and showed up first in high-end 486s and Pentium systems. On the Mac side of things there’s no E, they’re just referred to as IDE drives. SCSI, which is pronounced “scuzzy”, means Small Computer System Interface.
The essential difference is that SCSI drives are traditionally faster, although EIDE drives have caught up in the last 3 years. To use a SCSI drive on a PC, you’ll need a special SCSI controller card which runs between $150 and $300. The nifty thing with a SCSI is they have lots of room for add-on devices.
“SCSI can handle up to up to seven devices on a system. That includes SCSI CD-ROMs or tape backup systems plus hard drives. Or, if you prefer, you could install seven hard drives,” said Jim Hendy of Campus Computers in Edmonton.
Of course you’d have to have a lot of space and hard-drive bays in your computer case to do that. EIDE systems have room for up to four devices.
On the Mac, all new PowerPC machines use SCSI drives. The Performa series uses IDE drives, but has a SCSI port for an external hard drive, explained Carl Harr, general manager at Edmonton’s Westworld Computers.
SCSI systems, hard drives or other devices, on both the Macs and PCs are more expensive—about 20 to 30 per cent more.
As for specs on drives, the numbers that are important are seek times and transfer rates.
Seek time is the amount of time it takes for a hard drive to find the data that has been requested. Typically you’ll see seek times of between 8 milliseconds and 10 milliseconds. Of course the smaller the seek time number, the faster the drive.
Transfer rates are counted in megabytes per second. Typically you find SCSI drives have slightly faster transfer rates.
Also look for cache sizes on a hard drive. They go from none at all to typically 16K and then upward. The bigger the cache, the better.
“Home users don’t really need to be concerned about all those numbers,” said Hendy, “unless they’re going to do a lotof intense work. Companies typically run big database applications on SCSI drives.”
On the Macs, “if you intend to capture live video, you want a high-speed hard drive to prevent frame loss while writing to the drive,” said Harr. “If you are using a hard drive to store simple data like documents and graphics, then a lower speed drive will suffice.”
Jeremy Schmuland, a support technician at Edmonton’s Compu-Smart, gives a real-life example: “A 2.1 gigabyte Quantum Fireball sold at between $350-400 for the IDE version.They were replaced with a SCSI version which sells at $600-700. The access time is the same on both drives at 10.5 ms, but the data transfer rates are very different. The EIDE version has a maximum throughput of 16.6 megabytesper second, while the SCSI version has a transfer rate of 20 megs per second. You could then imagine that most home users wouldn’t pay an extra $250-300 for four megabytes.”
For lots more hard drive information, check out QuantamCorporation’s Storage Resource Centre on the web at http://www.quantum.com/.
In anticipation of new computers arriving for the holidays, a friend recently asked me how to move data from the old machine to a new one. The best way I’ve found is to use Touchstone Software’s FastMove! It promises a simple, one-button transfer.
Ever the pessimist when it comes to software marketers, I tried it. I installed copies on my home machine and on a laptop. The software comes with a parallel-to-parallel port transfer cable and, sure enough, I dumped about 100 megs per hour between the systems.
The software is both Windows 95 and Windows 3.1 compatible. It’s smart enough to offer you options when large file names from a Win 95 system are being sent to aWin 3.1 system that is expecting 8.3 file names. The software also has a utility to allow users to synchronize files between Zip drives and hard drives and integrates Touchstone Software’s virus checker PC-cillin 96.