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Hitachi to Release Half TB Drive Soon
samdu writes "Hitachi has announced plans to release a 7200 RPM 3.5 inch 500 GB hard drive in the first quarter of this year." Maybe this one won't require a new motherboard to use. I think I've replaced more mobo's to handle larger drives than I have to support faster CPUs.
While it's nice to something as fast as possible, is there a point to have a 3.0Gb/s interface to a product that can only handle 817Mb/s?
On drive cache.
Seagate Cheetah U320 SCSI drives are available in 15,000 RPM models. Much faster than that and you have problems with the spinning media deforming due to the stress.
Learning HOW to think is more important than learning WHAT to think.
Technical issues. It's hard to spin a platter at 10K RPM. It also requires cooling, and makes lots of noise too. 7200 is about the most you can use without having a fan blow on the HDD, and I would prefer not to because they get quite hot. I suppose the manufacturers picture lots of users buying a 10K RPM drive, sticking it into an under-ventilated box and getting a replacement a week later because it died from overheating.
There's also that RPM is not the only way of making things faster. Basically, the performance of a hard disk is determined by 3 variables:
Rotational latency: The time it takes for the disk to spin into the right position. That is, once the head is on the right place, this is how long it has to wait for the data to pass under it. More RPM translates into less rotational latency.
Seeking latency: The time it takes for the drive's assembly to get into the right position.
These two are often added up in the statistics. Solid state drives pretty much lack them. I'm setting up now a firewall that boots from CompactFlash on CF-IDE adapter, and it boots really fast despite a transfer rate of only 2 MB/s. Latency can add up to quite a lot.
Data rate: The speed at which the drive reads or writes data once everything is in the right place. This is a function of the RPM and data density. More speed means the data passes under the heads faster. More density means there's more data per square inch.
So, increasing RPM is one way of getting more performance. The other one is packing more data into the same place. Some drives have small platters for this reason. This also means that a bigger drive is often also faster than a smaller one, given identical RPM, platter size, and number of platters.
Only the 75GXP line was lemons. 120GXP and higher releases have been MUCH higher quality. (Don't argue with me about it as I have FOUR 7K250 drives, a DOZEN 120GXP drives and a DOZEN 180GXP drives in use 24x7 across a variety of desktop systems.)
Of course, operating system limits have nothing to do with motherboard limits. SATA uses 48-bit sector numbers IIRC, so that's a limit of 2^57 bytes. And 32-bit operating systems can use 64-bit filesystems (e.g. XFS) which have no practical size limits.