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The Coming of Serial ATA
GrendelT writes "Tom's Hardware has a review of the newest Serial ATA gadgets that are soon to hit the market. With speeds of 150Mb/s, thinner and longer cables, backwards compatibilty with Parallel ATA (what most of us have right now), and the option of being hot-pluggable, it seems the next step in storage technology is upon us."
Just in time for Doom 3!
Now we just need harddisks that can sustain a 150Mb/s data-transfer rate.
Now I gotta rewrite the app for espressos machine :\
This ought to help air-flow in the case a lot.
:)
My worst problem building mini-towers has been trying to tack the ribbon cables to the side where they won't block air, or run into a fan blade...
Screw the speed, etc... It's just a better cable
Why not use 1394 for internal devices as well as external? Is it too bloated/expensive?
-- Free speech is only free if your time is worth nothing.
Evan - needs to hit preview before submitting
serial cable to replace USB. oh wait...
ANYTHING to keep from scraping my damn knuckles or cracking fingernails when removing a drive is fine with me.
I would've been happy with a connector technology based on FireWire, but if this is cheaper, as easy to connect as FireWire, and no slower than current ATA, then break out the pinatas filled with old hard drives and the Louisville Sluggers.
Vos teneo officium eram periculosus ut vos recipero is.
This is going to be great for NAS applications and managing racks of drives. Ultrafast buses all to one and another. Great for network backup too. I havent looked at prices yet, but hopefuly it's not too expensive to implement in a home environment.
Come on guys, that is one of the biggest details on the story
150 Mb/sec seems to imply megabits. SerialATA can transer 150 megabytes/sec.
He said, "You'll be able to tell your grandchildren that you helped assemble the first NT supercomputer," and I cringed.
I realize this is to provide for the third voltage but I hope the power cable will still be small. Don't want to end up using up the same amount of space as Parallel ATA and be back to square one.
Eddy.WriteLinux.Com
I don't know why everyone else keeps just putting whatever they feel like but I always use these conventions when writing about data: mbps (ALL LOWERCASE) = megaBITS in BASE10 per second. MB/sec (BOTH UPPERCASE) = megaBYTES in BASE2 per second. Oh BTW, for those looking for controllers, 3ware, http://www.3ware.com has mentioned they'll have SerialATA versions of their RAID5 controllers in 4, 8, 12, and 16 channel versions next quarter via converter bridges, and probably native SATA-II controllers. What dissapoints me most is the power connector. 15 pins? Come on. I thought power was going to be included in the 7 pin cable. Now we have a power cable 2x larger than the data cable, and it's still going to be a pain.
Introducing the new Occam Fusion! Now with sqrt(-1) fewer blades!
...to be followed almost immediately by the posting of 50+ case mod articles on slashdot.
"Good things don't end with eum, they end with mania or teria." - H. Simpson
The IT7-MAX2 can therefore handle eight conventional IDE devices, as well as two serial ATA devices.
10 IDE devices. This is what I want to see with serial ata, is more devices. 4 IDE isnt enough, at least with newer motherboards with built in raid/fast ata, you get 8, but if you want 1 per channel for the best possible speed it limits it to 4.
Currently, I have 2 IDEs one on each fast ata on the mobo, and I get about 47 peak, and 34Meg sustained with IDE. Be nice when the 2 device on a channel is killed off.
The speed of this product really isn't the selling point, at least not now. Most 7200 ATA drives can't sustain much more than 40MB/s, let alone 150MB/s. The current ATA 133 is already overkill. The selling points are the small cable, the decreased voltage (signal voltage decreased from 5v to 150mv), the length increase, the future posibilities, and the adoption of much more popular serial design (similar to firewire and usb).
That an FireWire manufacturers don't want to give up their tasty tasty profit margins. The only reason ATA is even still around is because the drives are cheap. I'd bet if the manufacturers were willing to sell SCSI devices at consumer prices (say $25 to $40 more per drive over ATA to cover the cost of the electronics) most Slashdotters would be running SCSI and would scoff at ATA and lump it in with built-in video, built-in sound, and the built-in modems on consumer machines.
I hate ATA, but I still run it in my machines because I can't justify the 100%+ markup for SCSI devices. Heck, it's still really hard to get Command Tagged Queueing support on ATA devices, and the CTQ implementations I've seen have been at best half assed.
I read the internet for the articles.
Speed. Even the next generation of Firewire will only be 2/3 as fast as Serial ATA (as many have said, it's 150MB/s, not Mb/s). Not that there are any drives that fast yet...
is: $$$??
Err, yeah... I managed to get my Athlon XP installed and attached the heat-sink without crushing the core, but man was I unprepared for the hell that involved plugging in those IDE cables!
Damnit! Those basdards are always forcing us to upgrade! Change one part and you need a whole new motherboard! I have all these extra ISA alots and I can't use them? OK, so now I'm just being silly...
hit shift-reload in your browser. those are cached images
the direct linked ones do have hotlinking protection apparently
Quoted from tom:
However, this elegant new standard does have its limitations. Serial ATA adapters use the PCI bus, which restricts the theoretical maximum data transfer rate of 150 MByte/s to the 133 MByte/s that the PCI bus allows.
I bought an adaptec 29160 a while ago. The card is sort of extended for 64bit PCI. I went back to fry's for years after I bought it to find a desktop class mobo to support it.
All I could find was dual CPU mobo's with 160scsi already built in! Why isn't there a single CPU board that supports 64bit PCI?
Maybe I just haven't looked in a while, but I was at fry's last saturday (when I saw the via eden board) and looked for a 64bit PCI mobo for my p4, nothing but high end dual mobo's had it.
Anyone got any thoughts? Suggestions? Please?
Look at those benchmarks. If they can match a Parallel ATA drive with only 8 wires, imagine what they could do if they used as many as the parallel ATA drive.
Just say no to round ATA133 cables. Every other wire on an 80-wire IDE cable is a ground. It's there to shield the data wires from one another.
When you bunch the individual wires up like that, you destroy the shielding. At high data transfer speed, you are going to get CRC errors due to interference, and this means lower performance as the IDE controller has to deal with them.
Rounded cables are suitable for low speed applications like CDROM and floppy drives.
Parallel ATA has never been able to mix read/writes out to the bus like SCSI has*. Anyone know if Serial ATA is different because you don't daisy-chain SATA cables like Parallel-ATA does? Are SATA devices buffered from each other?
*SCSI has the ability to disconnect devices, meaning that you can send drive0 a read request & disconnect from the bus, and then send drive1 a write request while you're waiting for drive0's relatively slow mechanical storage to stream out the response. Parallel ATA makes the bus wait for a response from a read request before anything else happens, basically blocking off drive1 even though bus traffic is idle.
I've been reading through the postings and I read that article on Tom's this morning. I've been following Serial ATA for a while now and there is some information that is apparently obscure that most people dont understand...so...I will try to create a list of the good qualities of Serial ATA to help you guys sort through the crap:
1) It is backwards compatible with your current drives.
Now most of you might not care about this but it actually saves alot of money for motherboard makers when it comes to designing a board to support it. Less pins means less tracings which means lower development and production costs which means cheaper motherboards. Not to mention, manufacturers of drives dont have to seriously retool their lines and redesign their drives...which means no elevated hard drive cost when you buy new drives. Also there are adapters out there for current drives (as demonstrated in the article) so that you dont have to format and reinstall when you upgrade your motherboard.
2) It is built with the future in mind.
Much like original ATA, Serial ATA was designed with room to grow. Sure, it supports up to 150MB/s right now with no drives to go along with it...but when those drives come along (in 5+ years) it will be there to support it....and faster. The standard can ramp up in speeds.
3) Chipsets will now be easier to design.
With less pins to worry about in the design of the bridge chipset that serves as the interface for the drives, these interfaces become simpler to design...and you will be able to add more drives to the machine than ever before. You shalt no longer be limited to 4 drives in your box requiring a slow PCI adapter to connect them to (whoever thought that was a good idea anyways?).
4) Lower power requirements.
I shouldnt have to elaborate on that....I have to have a 450watt PSU in my current box just to handle the load. It will be nice when I can step that down to a 400watt. Nuff said.
5) HOT PLUGGABLE DRIVES!!!
You have no idea how long I have waited for this. Put a second drive in a removable slot....copy my 40GBs of 'files' onto it...take it over to a friends place...put the drive in...give him a copy of the 'files'. Oooooh....and backups to hard drives that you can easily remove and take to a safe deposit box. I don't really need to explain how beneficial this is.
6) Thin thin thin thin cables.
I have to run a water cooling kit in my PC because the airflow is so atrocious in my mid-tower with my RAID 0+1 system and 4 drives. 80 pin connectors have really needed to go for a long time. Rolled cables helped a bit but they are still thick and cumbersome. Of course now I stand the chance of confusing my CDROM audio connector with my ATA connector...but thats a small price to pay when i get another 30 CFM's through my box just by changing some cables around.
These are just a few of the reasons that serial ATA is a good good goooooooood thing.
Stop slamming what you dont understand.
Honesty may be the best policy, but apparently by elimination, dishonesty is the second best policy.
I have seen bonnie report ~ 40MB/s on a single IDE drive, that was around a year ago, so I imagine current model drives are faster. Too bad you spent so much on that fibre channel raid.
how are the Case modding geeks going to separate themselves from the rest of the mortal PC geeks if they can't be the only ones to have those neat rounded IDE cables and everybody has practical Serial ATA ones?
Seriously, I think that this will clear up so much space in the case that modding will gain a whole new element.
I can just picture a Desk with the PC integrated wholly into it, without the limitations on the IDE cables being so close to the controller cards the parts can be spread out much more, into more ergonomic and aesthetically pleasing PC designs...
I personally just want an external serial ATA adapter so I can just use a "Standard" hard drive for transporting data vs the USB ones or Optical media.
wordtrip.com
Apple, when designing the Firewire physical port looked into what it would take to build a rugged, tough, port that would accept the rigors of being connected and unconnected repeatedly. In their search, the y found that Nintendo had already done this with the design of their GameBoy link cables.. and thus, used the Nin design for firewire (well, slightly modified).
And let me tell you - how much i plug in and unplug FW devices, i'm sure glad that its like that..
knowing the PC users that i do (you know, covers never on, harddrives mounted with paper wrap so as to prevent shorting the system, etc...) - i can't believe that out of all the comments so far, no one is screaming bloody murder about the tinsey-weensy little detail that the fscking cable kept coming undone - and how insanely stupid that is.
Its written off as "a prototype problem" - i say that Tom's Hardware has done a lousy job of highlighing this and has done a disservice in not making it a major issue.
of course - this is a PC review site - and Tom's is probably used to things crashing and just not working all the time.
guns kill people like spoons make Rosie O'Donnell fat.
A RAID mirror will only save you from hardware failure.
If you accidentally nuke your files, get hit by a virus, or Windows eats intself (INACCESSIBLE_BOOT_DEVICE), you will have two very excellent copies of the same missing/damaged data.
You need real backups, not a RAID mirror.
"The reason this is useful is that you have a larger bus bandwidth, not that it benefits any one particular device."
Too bad Serial ATA is a point-to-point bus. One device per host interface.
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
"When you bunch the individual wires up like that, you destroy the shielding."
Good round IDE cables have shielding around individual wires, and between rows, to keep things working. Like most things with the IBM-PC, there is considerable variation in quality (and price). People need to realize that getting an I/O cable for a buck might not be a good thing...
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
actualy they sidestep the issue by making it point to point and using only one device per channel. Since putting extra channels in the silicon is extremely cheap they did the right thing and moved the work to the controller, if you want to support 16 channels then you need a controller that is capable of 16 channels.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Disks are as unreliable as ever and are not close to following moore's law in speed up.
Well, Moore's law was actually about the number of transistors on a die and not about speed at all. While drives have not gotten significantly faster over the years, their density has grown by an unbelievable amount. The first hard drive I ever used was on a Mac. That was probably 15 years ago, and was a 20MB drive. I can now go buy a 200GB drive (10,000 times bigger!) for less money in a smaller case. And the fact that you can even build a system which can hold a hundred gigs speaks wonders for the reliability of hard drives. Can you imagine the uptime on a drive farm of 10,000 drives? Do you know how many would fail every hour? It would have been a challenge to build a 200GB data farm at any price in 1985. It is a shame about the speed though. Seek times are what, like 10% of what they used to be?
actually what you want is what netapp offers, raid mirroring across units with redundancy everywhere and snapshot features that keep hourly and daily backups going back 8 hours and 7 days in our setup. We of course back this up to tape for archival storage, but when the sales executive nukes that presentation that they have to give in 15 minutes I calmly re-explain how to copy the files out of the read only snapshot directory for the 3rd time this quarter =) Do we pay for it, sure as far as cost/MB goes it's probably horrible, but the data is always there, and for us that is most important, and besides they basically remove a tape person and replace him with better hardware.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
"Apple, when designing the Firewire physical port looked into what it would take to build a rugged, tough, port that would accept the rigors of being connected and unconnected repeatedly."
Which makes sense. ATA (in any form), however, is not intended to be connected and unconnected repeatedly. Anyone who has ever bent the pins on a drive, or pulled the IDC right off the ribbon, can tell you it has been this way from day one. ATA is supposed to live inside the computer and be touched only rarely.
That being said, from what I've read, the new Serial ATA cables are likely to stand up to abuse better than the ribbons we have now. The connectors are smaller (= less friction = less mechanical stress), and there are no pins -- only edge contacts. But it still is not designed for abuse. Don't do that, then.
"...the fscking cable kept coming undone... written off as 'a prototype problem'..."
Dude, have you ever seen prototype hardware before? That sort of thing is normal. I've seen prototype systems with so many ECO wires that the cover wouldn't close. I've seen boards with parts missing. You cannot base anything on the quality of this sort of stuff. It is the hardware equivalent of a "beta" or "development" release.
As for coverage, Tom devoted a whole page to it -- what more do you want?
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
"The real knuckle busters are really tight power connectors on drives. You know, the kind that you need a crowbar to remove."
Worse still is when you end up removing the power socket from the hard disk PCB instead....
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
GREAT! Now every legacy drive gets to think that it's the master. This solves the one reason I had SCSI for many years in my home box, extra cost be damned.
I wouldn't want people fucking things up in their boxes because their drive manufacture told them it's ok to mess with it while it's turned on.
"Ask not what your country can do for you." --John F. Kennedy
Yes- people abuse Moore's law quite often. If you read a lot of tech publications, it might seem like Moore's law means that everything in your computer gets twice as fast, costs half as much, runs twice as cool, and gets twice as sexy every 18 months. Increasing the number of transistors on a die can contribute to those, but thats not what Moore's law is about.
"The defense of freedom requires the advance of freedom" - George W Bush
Because its software compatible with PATA drives, it uses the same interrupt solutions as PATA controllers. In legacy mode, it will use IRQ 14 and 15 (and be limited to 4 devices), and in native mode all devices will share a PCI interrupt (like PIRQC) that can be routed whereever you want. Each drive does not need its own interrupt.
"The defense of freedom requires the advance of freedom" - George W Bush
"...is poking around inside your machine when it's still turned on a good idea?"
;-) (With apologies to Scott Adams.)
Hot-swap is like nuclear power: It can be used for good or evil.
Seriously, hot-swap is probably not something you want to give to the average luser. I tell some of people to shutdown their computers before swapping anything (USB, PCMCIA, etc.) just because it is easier for them to understand.
In a server situation, though, hot-swap is often a requirement. Redundant disks really want to go along with hot-swap. Even the ability to expand storage while online is useful. High-end servers these days have hot-swap PCI; hot-swap disks are expected as a matter of course.
dragonhawk@iname.microsoft.com
I do not like Microsoft. Remove them from my email address.
For FireWire and USB, in contrast, there is just a lot more to configure and a lot more driver support needed, and it's still hard to boot from them.
That's probably a hardware limitation actually - your system probably only routes a maximum of 4 IRQs to the PCI slots, AGP slots and on-board devices like USB etc.
2x Socket A
2x 64 bit 66 MHz PCI slots
4x 32 bit 33 MHz PCI slots
4x 266MHz DDR slots
Available from Tyan, Asus, Gigabyte, Abit, etc.
___
If you think big enough, you'll never have to do it.
(see subject) 150MB/s is just a gimmick for the people who don't know any better. The real advantage (to me) is hot-pluggability, and (as already mentioned) thinner & longer cables + backwards compatibility with standard IDE.
___
If you think big enough, you'll never have to do it.
I know there will be Old Drive -> New Bus adapters, but will I be able to get something for the other way?
For example, if the drive dies in my only SATA machine, am I screwed, or will I be able to use an adapter for PATA?
-twb
You do know that serial ATA supports only one drive per channel, don't you?
___
If you think big enough, you'll never have to do it.
Latency may be slightly less on IDE than similar SCSI drives, but 1) you can get 15000 RPM scsi drives and only 7200 RPM IDE, and 2) the effective latency on SCSI can be much less if you have a drive that effectively reorders requests to minimise seeking. The OS can do some of this, but it doesn't necessarily know the best way to access a particular drive.
What we really need is for all this research going into increasing disk density, to get applied to tape. I want a $1000 tape drive that can write a terabyte to a $10 tape cartridge.
As copyright owner of this comment, I authorize everyone to defeat any technological measure which limits access to it.
IDE cables (100 & 133) ARE available in rounded braided cables. Braiding the cable, when done correctly, cancels out most of the crosstalk that is the reason for that extra shielding. SCSI round cables are braided for much the same reason.
Find out about my new childrens book: SS Death Camp Criminal Batallion Go To Monte Carlo For The Massacre
>>When you have 2+ drives running with over 50MB/s bursts, though, it's nice to know there's some room there.
That's true... I was mainly thinking sustained.
>>Of course, the next generation of firewire goes a bit further than you have stated (about 4x)
Hmmm... that's what you get from trusting second-hand information. Someone in another thread said that the next generation would be 100 MB/s, and I didn't know better so I just used that information here.
I did make the file 2x memory size... dumb ass. hdparm -Tt by the way reports ~ 320MB/s which is the cache speed.