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eSATA External Storage Drive Reviewed
Tom's Hardware has a practical look at an eSATA drive offering from Taiwanese storage firm Thecus. From the article: "Thecus' N2050 is one of the first external twin-drive RAID boxes that uses eSATA. As expected, its performance was far better than what USB 2.0 offers. The end result is impressive. The date transfer rate of 30 MB/s that USB 2.0 offers does indeed pale in comparison to 100 MB/s for eSATA, while the WD1500 drives are capable of delivering even better performance in RAID 0. It is also good to see that Thecus did not throw the USB 2.0 interface away, because it is a nice backup interface whenyou want to use the device with other computers via USB 2.0."
eSATA enclosures have been around for a while. The larger ones tend to have a port multiplier built in, which lets you use up to 5 drives with a single channel. This is the one I am after, but sadly the company will not ship to the UK.
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http://www.cooldrives.com/mac-port-multiplier-sat
It's sure as heck nice to have both.
A lot of technically inclined people, myself included, use an external hard drive for backup purposes. It would be really nice to cut the time needed to perform a full backup in half.
Just because it's easy and portable doesn't make it for the non-techs only.
Also, mentioned in the article... the SATA bus boasts a wonderful 3Gb/s (or 300MB/s). This however, is not the bottle neck when it comes to performence. As the article mentions, the top SATA drives on the market today only get about 85MB/s read/write to the disk. So although you may get 300MB/s from the disk cache, and the controller, you'll never really get 300MB/s. Still, it's miles from Ultra-ATA.
The upcoming (high def) TiVo Series 3 has an e-SATA port. Adding more recording space will be a whole lot easier than it was before, especially for the less adventurous folks.
And why does the type of home user who shuns opening his or her case need mind-blowing performance?
And why do you assume that an user who requires an external drive is a "home user who shuns opening his or her case"? Poppycock.
Scenario 1: All the drive bays in your machine are full, and Firewire's too slow because you move big files around.
Scenario 2: The data on the drive needs to go somewhere else.
My desktop drive bays are full, but for me, I see this as a great replacement for backup tape drives, w/o having to sacrifice throughput. Assuming that the enclosure will fit in a safety deposit box, a couple of these could replace my current network backup hardware.
It is true that a single drive cannot saturate the SATA channel. (85MB/s is actually a _very_ generous estimate. Typical performance is closer to 50-60MB/s). So, SATA certainly doesn't need more bandwidth in the near future. However, for eSATA, the extra bandwidth is _very_ useful. It would allow manufacturers to produce RAIDs with eSATA ports instead of SCSI or FC. (Right now, you still need a SCSI or FC card if you want to get any sort of performance). This would effectively commoditise the low-end RAID market, which is a very welcome development.
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If you think big enough, you'll never have to do it.
Gotta read it literally. No mention of redundancy. Of course, the missing (but, I guess, implied) extra sentence telling us that "only" half of our data would be gone wouldn't have killed them.
Every single review of storage technologies I have read in the past 2 years state at least one (IMHO very important) incorrect fact. This is no exception with this one:
Page 2: "The fastest 3.5" SATA drives do not exceed 85 MB/s. A data transfer rate of 300 MB/s between a PC and a SATA drive cannot thus be matched by the speed of a SATA drive." Yes it can. When data is exchanged to/from the disk's cache, data throughput of 250+ MB/s can be achieved for a fraction of a second. Even if it's only for a fraction of a second, it is still important (else manufacturers would not even put cache memory on disks).
eSATA is cute and all, but nothing's ever stopped me from routing regular SATA cables out the back of the case, to a nice external hot-swap drive tower. Many higher-end motherboards even come with a little bracket for external SATA ports. While I understand that eSATA is somewhat improved for signal integrity and ease of use (grippy connectors), it doesn't seem like such a big deal to me. I haven't seen a single motherboard with eSATA yet, though some "platinum edition" boards do have a true SATA jack on the backplane. If you want both simplicity and speed. For idiot-proof simplicity there's the ubiquitous USB. For speed there's the real SATA. Is there really anything in between that needs eSATA at all ?
-Billco, Fnarg.com
Just because it's easy and portable doesn't make it for the non-techs only.
In fact, that's what makes tech cheaper for us...it's the rest of the non-techs buying a new computer whenever theirs is "broken" from too much spyware, or needs a little more RAM. If everyone bought PC hardware only when needed and jealously guarded every CPU cycle, PCs would still be as expensive as they were 20 years ago.