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15k RPM IDE Hard Drives?
OutRigged asks: "SCSI hard drives have had speeds in excess of 10,000RPM for years, yet IDE has always been stuck at 7200RPM. Is there some kind of technical reason IDE drives don't go above 7200RPM? I can't imagine cost being that big of an issue, and the connection is certainly not a problem, with Parallel ATA capable, at least theoretically, of speeds over 100MB, and Serial ATA capable of even more. With hard drives now reaching sizes in excess of 300GB, don't you think we need a speed increase?" If you are wondering what the terms "Parallel ATA" and "Serial ATA" refer to, check out this article.
Would be interesting, however HDD read heads are different to CD's. A CD is a moving laser that goes in and out, a HDD head is more like a record player - you could get two heads on there, physically, you may even be able to get three, but they would be running very close to each other.
Can anyone with a clue answer this question?
It would reduce reliability, as most catestrophic failures of hard disks involve head crash of some sort. Twice as many moving parts is bad, mmmkkkay. :)
The head assembly also takes up quite a bit of room. You would probably have to go to a half height 5-1/4 form factor like old SCSI disks were.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
It IS expense...so often we forget, but only recently were harddrive manufacturers having problems with their 7200RPM and in some cases even 5400RPM drives. The reason is heat. If you check around, you'll find that the largest 15000RPM drive is made by Seagate (it's ~80GB and it's ~$1000)...why???
When you raise the number of bits per inch of storage surface you create more stress and heat. When you raise the RPMs you create more heat (alot @15000RPM). The overall effect is that you can't use the cheap parts that are used in most IDE drives...every piece of the drive must be manufactured to the highest specifications. Motors have to be of the highest quality. Hydrodynamic bearings must be used instead of metal ball-bearings...this all increases the cost (as it pushes the technology).
The reason why these faster drives are not sold as IDE is simple. Anyone who is willing to pay $1000 for a ~80GB harddrive is also willing to pay $75 for a decent controller card (if it's not already built into their workstation).
How many ppl are going to be willing to pay $1000 for an 80GB IDE drive when they can buy a 300GB drive for 1/3 the cost? The end result is that most consumers simply don't care about the speed...the majority of IDE drives go into OEM systems and the consumer probably won't know if they put a 4500RPM drive in the system.
So, why not get the best of both worlds. Buy a 20GB 15000RPM SCSI and put your system files and most widely used apps on that (~$130 for a 18G Seagate). And then buy a larger IDE drive for archives.
When you think about it, you shouldn't need more than 20GB for your system, apps, and maybe a few games.
As far as the slower IDE drive, just spend your money on more RAM for the system and increase the cache. And don't rely on the CPU intensive built-in IDE controller on most Intel/AMD motherboards...buy a decent controller card instead.
And if you really want to get ~15000RPM with IDE technology, just get an IDE RAID controller and use striping...using this method you can actually get to much higher theoretical speeds than a single 15000RPM drive. with 4 7200RPM drives you could get up to a theoretical speed of 28800RPM!!!
Market forces drive IDE drives to be built as cheaply as possible while still having the right buzzwords to make consumers believe they're faster than their competitor. RPMs higher than 7200 still don't register with the mass populace, so it's not yet a factor.
SCSI hard drives are all about top-end performance. That's why some SCSI drives cost $1,500 for the same capacity as a $150 IDE drive. It's about being able to reliably move the platter at twice the speed of IDE, and having the correct drive logic and buffer memory to make it useful in the real world, getting very high MTBF numbers, etc..
Comparing typical IDE drives versus high-end SCSI (or FC for that matter) drives is like comparing small asian economy cars with the contenders in the F1 racing series. They have entirely different goals.
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