Rudy

In an effort to help determine what drives work better than others, I thought this chart comparing the Maximum Power Consumption of various 2.5" drives might help us out...

jfisher08

great info Rudy and here is a list of drives I have tried with no success:

Fujitsu MHV2100AT
Toshiba MK3021GAS
Hitachi HTS548040M9AT00

Rudy

I'm going blind trying to see if your drives are listed on my table. Do you see them?

I might see if I can get my hands on the first or second drive listed (1.9 W maximum consumption) just to see if it works reliably in the car...

jfisher08

The Fujitsu is on there 3.1W.
I am going to try the first one should have it mid next week if you want to wait to see how it works.

Rudy

That sounds like a plan to me!

I did some further research on my Hitachi model number (the part number I told you before was on the box but now I'm looking at the drive itself) which turns out to be: HTS541280H9AT00 (or 5K120 series).

According to Hitachi's datasheet (link: http://www.hitachigst.com/hdd/support/5k120/5k120.htm), my drive's maximum power consumption at startup could be as high as 5.0W but I find that to be pretty high considering my drive works most of the time. It is, however, a 5400 rpm drive so I think I can do much better if I go with something else.

The datasheet for the Hitachi 4K120 series drive (the first one on the table, model number HTS421210H9AT00) shows the maximum power consumption at startup to be 4.5W so it's clearly a little better but I'm not sure how much that .5W is going to matter. (datasheet link: http://www.hitachigst.com/tech/techlib.nsf...20_DS_FINAL.pdf)

Keep us posted on your findings!

BTW, if anyone is interested in deciphering the Hitachi Travelstar model numbers, here's the key:

example: HTS421212H9AT00 = 120GB/8MB

H = Hitachi
T = Travelstar
S = Standard
42 = 4200 RPM
12 = Full capacity - 120GB
12 = Capacity this model 12 =120GB (10 = 100GB, 80 = 80GB, 60 = 60G
H = Generation code
9 = 9.5mm z - height
AT = ATA interface
0 = Reserved
0 = Reserved

bruce_miranda

For simple applications like this you should try and find the lower 4200RPM or 5400RPM drives instead of the faster 7200RPM. Normally, the lower the RPM the lesser the power consumption. Besides you will never need the fast access speeds that the 7200RPM is designed for. Also 4200RPM drives are cooler and queiter too. This is one of the reasons a Sky+ box works with a 5400RPM drive but the moment you swap it for something like the 7200RPM drives you get the cooling fan on all the time because of the extra current draw. 0.5W makes a lot of difference on a USB port. The USB port was never designed with the intention to power up big devices.

Russ1974: I made a hidden 12V socket in the center console exactly the wat you are planning to, there is enough space to house one in there. I made it to power my WM5 phone using a normal cigratte lighter plug. I just connected a female cigratte lighter socket that I bought from Maplins to the back to the rear facing sockets that I was installing myself at the time. But just be careful that you don't obstruct the handbrake cables and also tie your socket down and wrap it with some cloth/felt etc. Otherwise you may hear a rattling sound inside the car.

bob.a

I see from the Hitachi website Rudy quoted that they also supply 1.8" drives up tp 80GB. At the drive level, at least, these need much less power for operation and impose a far lower peak consumption when starting.

http://www.hitachigst.com/tech/techlib.nsf...le/C3K80_DS.pdf

Does anyone know of a power efficient USB enclosures for these gadgets? Unlike standard 2.5" hdds, they require 3.3V rather than the 5V provided directly by the USB socket.

Rudy

Good idea! I think this might work very well. It looks as if the startup maximum power is only 1.3W.

Also, there may be other enclosures available but the first couple I found are right here:
http://www.cputopia.com/green-1-8inch-usb-...drive-case.html
http://www.sfcable.com/cable/p/ECS-USB20-18S.html

jfisher08

Update
Tried bob.a's idea and purchased a 1.8 drive and a portable enclosure so far it is working great, finally. One question do I need to unplug the drive every time a get out of the car since it stays on?

Thanks for everyone's help and hope this helps others not have to go through what I did.

Rudy

No need to unplug -- the drive will shut down once the car goes into sleep mode (around 15 minutes or so...)