Where can i find a good list of HDDs that will automatically spin down.
I cant find good search terms for google.
I want it for an usb external HDD. (also can you recommend some good cool and quiet USB external enclosures?)
Thanks
Harddrives with automatic Spin Down for external USB HDD
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Doesn't external USB HDDs spin down like any other HDD? Is it because it's USB and not IDE?
I just bought two Asaka eSATA/USB2 enclosures. If you can, go for an eSATA box. Through the eSATA interface you can make the HDD spin down via the OS, the HDD is like any other SATA HDD in your system.
I just bought two Asaka eSATA/USB2 enclosures. If you can, go for an eSATA box. Through the eSATA interface you can make the HDD spin down via the OS, the HDD is like any other SATA HDD in your system.
Vicotnik: "Doesn't external USB HDDs spin down like any other HDD? Is it because it's USB and not IDE?"
Most USB enclosures only transfer data and cannot relay STAND-BY commands from the host to the drive. Windows power management is a counter that is kept in computers RAM and the drives are spun down by the OS when the timer reaches a value set by the user.
IDE drives operating in USB enclosures need a timer implemented on the hardware itself. Probably the best way is to select a drive that has load/unload technology (instead of being based on traditional contact start/stop (CSS)) and support for APM (Advanced Power Management). APM allows end-user configuration of power saving modes like unload idle and low-rpm idle. Only manufacturer that I know of using such technology in 3.5" drives is Hitachi. Newest WDs (WDxxxxAAxx) should also have unload ramps but AFAIK they don't support APM feature.
There's also Maxtor DiamondMax +8 and DiamondMax 17. They have unload ramps as well. +8 has a inner diameter implementation and DM17 has a Hitachi-style outer diameter ramp. I don't know about their support for APM... and I would stay clear of DM+8. I've heard it's very unreliable, much like it's bigger cousin DM+9.
But anyway: any Hitachi drive should be a safe buy as they all have APM. For external use without fan cooling, I'd choose 7K160 (80 or 160GB) or T7K500 (320, 400, 500GB). In 250GB capacity point, there's pretty much identical drives from T7K250 and T7K500 series (just don't buy a 7K250 as those have an extra platter). Stay away from 7K400, 7K500 and E7K500 as they have five (5) platters and are not suitable for passively cooled enclosures.
GLO: "Also are there any external HDD cases that can run off the USB as its poiwer supply?"
Yes, but they are all 2.5" enclosures. Care to guess why? There's several reasons:
1) 2.5" drives use 5V power. 3.5" drives use 5V for the electrics and 12V for the mechanics. USB port offers only 5V power output.
2) USB ports offer at least 500mA of current at 5V voltage (which is 2.5 watts of power). For short periods of time (like spin-up of 2.5" drive), most ports are able to offer slightly higher current, but 3.5" drives use up to 30 watts of power during spin-up so it's way above the capabilities of a USB port to supply. Even after the high-current spin-up phase, 3.5" drives use 5 to 10 watts on idle and 10 to 15 watts while seeking (compared to 2.5" drives which use less than a watt on idle and a few watts on spin-up and seeking).
So, it's a pure impossibility to spin-up the drive from USB power. Even with some battery back-up power to handle high spin-up current and a voltage increase circuit to supply the 3.5" unit with 12 volts (which USB port cannot supply), it'd still be impossible to keep it idling. It would eventually drain the battery/capacitor, no matter how high capacity it had.
Most USB enclosures only transfer data and cannot relay STAND-BY commands from the host to the drive. Windows power management is a counter that is kept in computers RAM and the drives are spun down by the OS when the timer reaches a value set by the user.
IDE drives operating in USB enclosures need a timer implemented on the hardware itself. Probably the best way is to select a drive that has load/unload technology (instead of being based on traditional contact start/stop (CSS)) and support for APM (Advanced Power Management). APM allows end-user configuration of power saving modes like unload idle and low-rpm idle. Only manufacturer that I know of using such technology in 3.5" drives is Hitachi. Newest WDs (WDxxxxAAxx) should also have unload ramps but AFAIK they don't support APM feature.
There's also Maxtor DiamondMax +8 and DiamondMax 17. They have unload ramps as well. +8 has a inner diameter implementation and DM17 has a Hitachi-style outer diameter ramp. I don't know about their support for APM... and I would stay clear of DM+8. I've heard it's very unreliable, much like it's bigger cousin DM+9.
But anyway: any Hitachi drive should be a safe buy as they all have APM. For external use without fan cooling, I'd choose 7K160 (80 or 160GB) or T7K500 (320, 400, 500GB). In 250GB capacity point, there's pretty much identical drives from T7K250 and T7K500 series (just don't buy a 7K250 as those have an extra platter). Stay away from 7K400, 7K500 and E7K500 as they have five (5) platters and are not suitable for passively cooled enclosures.
GLO: "Also are there any external HDD cases that can run off the USB as its poiwer supply?"
Yes, but they are all 2.5" enclosures. Care to guess why? There's several reasons:
1) 2.5" drives use 5V power. 3.5" drives use 5V for the electrics and 12V for the mechanics. USB port offers only 5V power output.
2) USB ports offer at least 500mA of current at 5V voltage (which is 2.5 watts of power). For short periods of time (like spin-up of 2.5" drive), most ports are able to offer slightly higher current, but 3.5" drives use up to 30 watts of power during spin-up so it's way above the capabilities of a USB port to supply. Even after the high-current spin-up phase, 3.5" drives use 5 to 10 watts on idle and 10 to 15 watts while seeking (compared to 2.5" drives which use less than a watt on idle and a few watts on spin-up and seeking).
So, it's a pure impossibility to spin-up the drive from USB power. Even with some battery back-up power to handle high spin-up current and a voltage increase circuit to supply the 3.5" unit with 12 volts (which USB port cannot supply), it'd still be impossible to keep it idling. It would eventually drain the battery/capacitor, no matter how high capacity it had.
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Devonavar
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As far as I know, the only hard drives that will spin down automatically are Hitachis with APM, although this will only drop the RPM to ~3600RPM, not spin it down entirely. It's quite possible that other drives have this capability, as it is built into one of the ATA specs, but I've never managed to find a utility that will enable it for consumer use. I think this feature only gets used in server farms, so you'll probably have a hard time finding it.
You won't find a USB-only powered enclosure; the USB power specs aren't up to the task. This is a limitation of USB, not the design of the enclosure. The one exception is an enclosure that accepts a 2.5" drive — I believe Seagate makes an enclosure that only optionally requires external power. Even then, not all systems are capable of supplying adequate power, so Seagate supplies a "split" USB cable that allows a second USB port to be used. I'm not sure how reliable this approach is. I get the feeling it's not perfect, since Seagate included a power adaptor anyway.
You won't find a USB-only powered enclosure; the USB power specs aren't up to the task. This is a limitation of USB, not the design of the enclosure. The one exception is an enclosure that accepts a 2.5" drive — I believe Seagate makes an enclosure that only optionally requires external power. Even then, not all systems are capable of supplying adequate power, so Seagate supplies a "split" USB cable that allows a second USB port to be used. I'm not sure how reliable this approach is. I get the feeling it's not perfect, since Seagate included a power adaptor anyway.
I use a 2.5" laptor drive (an old Hitachi Travelstar 12GN, 4200rpm, BB, 2-platter, 12GB) as a USB drive in a Mapower enclosure. 12GN uses so little power it spins up 99% of the time even without the split cable. Using split cable just makes it even more certain + allows use of drive with higher rpm.
EDIT: It's a IBM Travelstar 12GN. IBM's HDD division hadn't yet been acquired by Hitachi at the time the drive was made. And an old drive it is. All current laptop drives (and >99% of desktop drives) use fluid bearings. Maxtor DM16 250 and 300GB variants are probably the only exceptions... even they are likely out of manufacture. (DM16 is a series of drives that use 5400rpm. Lower capacity variants have FDBs, higher capacity variants are equipped with old-style BBs. I own one 300GB variant - It has become quite noisy already.)
EDIT: It's a IBM Travelstar 12GN. IBM's HDD division hadn't yet been acquired by Hitachi at the time the drive was made. And an old drive it is. All current laptop drives (and >99% of desktop drives) use fluid bearings. Maxtor DM16 250 and 300GB variants are probably the only exceptions... even they are likely out of manufacture. (DM16 is a series of drives that use 5400rpm. Lower capacity variants have FDBs, higher capacity variants are equipped with old-style BBs. I own one 300GB variant - It has become quite noisy already.)
Last edited by whiic on Fri Dec 29, 2006 4:12 pm, edited 1 time in total.
My experience is that Seagate USB drives (both the 2.5 and 3.5" variants) spin down -although whether this is due to windows spin down times, or something in the drives I don't know -I've never tested it. The Seagate 2.5" USB drives power from almost all standard compliant USB ports, the maximum current draw is indeed 650mA as listed in the drive specification, however this is only drawn during spinup. Most of the time, the drive takes about 1-200mA (measurements were not very precise because I didn't need to know closer than the nearest 100mA.). It is also worth noting that the 2.5" Seagates seem quite capable of letting you know if you are giving it an innapropriate power supply -although the behaviour does not seem to be documented anywhere.
Bluefront: "FWIW.....WD external USB "My Book" drives will spin down to zero rpms after a few minutes"
I have no experience with WD externals. Maxtor OneTouches have some built-in spindown counter as well. The timer target value can be configured from some minutes to several hours of idling before power off but this requires installing special Windows software. Using WinXP's built-in drivers you can use OneTouch normally but cannot use the OneTouch "back-up" button or configure idle timer. With the special software installed, the drive will spin down on Windows exit.
I like the stock USB mass storage drives better than Maxtor's software and replacement drivers. I don't like the HDDs spinning down on computer shutdown. Why? Because it powers down on reboot as well! And powers back up just a few seconds later. Quite a no-brainer.
This is why I installed the software, configured a idle time counter, then uninstalled the software. Built-in idle counter remains active but can no longer be changed + no spindown on reboot. (I didn't technically uninstall the driver but made a fresh Windows installation.)
I use a 3 hour idle timer. It's a long one but I don't like my HDD constantly spinning up and down, especially because Maxtors are contact start/stop (CSS) based drives and read/write heads land on the platter when spun down. The 3 hour idle timer is merely present to allow the drives to spin down in case of OS crashing and freezing. If I leave the computer on for a week unattended, I'd rather not leave the HDD spinning for a week or so with no reason. (I leave the computer on 24/7 to Fold and share files. Due to that, the USB drives are powered on most of the time.)
I do use more aggressive power management on my Hitachi drives. They are not CSS but load/unload type HDDs, so the R/W heads never make contact with the platters and spindown/-up causes less wear. Also reducing rpm to 60...65% or around 4500rpm(*) causes less wear on spin-up than completely halting the spindle. Due to this, I use the most aggressive power management supported:
2 minutes of idle - heads unloaded.
10 minute of idle (2+8 mins) - low rpm mode.
Even though it's not completely spun down, it's almost inaudible (slight squeel from electronics), runs noticeably cooler and is a bit safer to relocate as the heads are protected from head crashes. (It's not as safe to move around than a completely spun down drive, but you can't move a spun down drive quite far either way. (Remember that USB cable is only 2 meters long and it can't be disconnected without first releasing it from the system. Otherwise some data loss may occur, even if the drive has spun down.)
(*) source: OEM specification of 7K80, 7K250, 7K400 and T7K250 contain these numbers. Those are all separate documents.
Where does that 3600rpm come from, Devonavar?
[Romeo]: "It is also worth noting that the 2.5" Seagates seem quite capable of letting you know if you are giving it an innapropriate power supply -although the behaviour does not seem to be documented anywhere."
How does a Seagate laptor drive react? My 12GN only sits there silently, with enclosures HDD activity LED lit continuously, no sounds coming out of the enclosure. (And believe you me: you hear it when 12GN has spun up. It's extremely noisy due to worn-out bearings.)
I have no experience with WD externals. Maxtor OneTouches have some built-in spindown counter as well. The timer target value can be configured from some minutes to several hours of idling before power off but this requires installing special Windows software. Using WinXP's built-in drivers you can use OneTouch normally but cannot use the OneTouch "back-up" button or configure idle timer. With the special software installed, the drive will spin down on Windows exit.
I like the stock USB mass storage drives better than Maxtor's software and replacement drivers. I don't like the HDDs spinning down on computer shutdown. Why? Because it powers down on reboot as well! And powers back up just a few seconds later. Quite a no-brainer.
This is why I installed the software, configured a idle time counter, then uninstalled the software. Built-in idle counter remains active but can no longer be changed + no spindown on reboot. (I didn't technically uninstall the driver but made a fresh Windows installation.)
I use a 3 hour idle timer. It's a long one but I don't like my HDD constantly spinning up and down, especially because Maxtors are contact start/stop (CSS) based drives and read/write heads land on the platter when spun down. The 3 hour idle timer is merely present to allow the drives to spin down in case of OS crashing and freezing. If I leave the computer on for a week unattended, I'd rather not leave the HDD spinning for a week or so with no reason. (I leave the computer on 24/7 to Fold and share files. Due to that, the USB drives are powered on most of the time.)
I do use more aggressive power management on my Hitachi drives. They are not CSS but load/unload type HDDs, so the R/W heads never make contact with the platters and spindown/-up causes less wear. Also reducing rpm to 60...65% or around 4500rpm(*) causes less wear on spin-up than completely halting the spindle. Due to this, I use the most aggressive power management supported:
2 minutes of idle - heads unloaded.
10 minute of idle (2+8 mins) - low rpm mode.
Even though it's not completely spun down, it's almost inaudible (slight squeel from electronics), runs noticeably cooler and is a bit safer to relocate as the heads are protected from head crashes. (It's not as safe to move around than a completely spun down drive, but you can't move a spun down drive quite far either way. (Remember that USB cable is only 2 meters long and it can't be disconnected without first releasing it from the system. Otherwise some data loss may occur, even if the drive has spun down.)
(*) source: OEM specification of 7K80, 7K250, 7K400 and T7K250 contain these numbers. Those are all separate documents.
Where does that 3600rpm come from, Devonavar?
[Romeo]: "It is also worth noting that the 2.5" Seagates seem quite capable of letting you know if you are giving it an innapropriate power supply -although the behaviour does not seem to be documented anywhere."
How does a Seagate laptor drive react? My 12GN only sits there silently, with enclosures HDD activity LED lit continuously, no sounds coming out of the enclosure. (And believe you me: you hear it when 12GN has spun up. It's extremely noisy due to worn-out bearings.)
Just to be clear, I'm talking about the Seagate branded USB drives, not a Seagate drive in a third party enclosure. The Seagate drives blink the LED regularly and apparently also have a piezo (I think that the piezo triggered with low voltage, but am not sure off the top of my head)whiic wrote: [Romeo]: "It is also worth noting that the 2.5" Seagates seem quite capable of letting you know if you are giving it an innapropriate power supply -although the behaviour does not seem to be documented anywhere."
How does a Seagate laptor drive react? My 12GN only sits there silently, with enclosures HDD activity LED lit continuously, no sounds coming out of the enclosure. (And believe you me: you hear it when 12GN has spun up. It's extremely noisy due to worn-out bearings.)
