I have looked at the hard drives that come in my Thinkpad T40s. They appear to be standard drives. One is a Fujitsu IDE drive the other is an IBM Travelstar drive. I believe the only thing they do is retract the heads to a non writeable spot on the drives. (remember the old park programs?) So, I don't believe there are any theortical differences. Having said that, I have some Panasonic Toughbook laptops and their drives although standard, appear to be enclosed in an additional housing that provides an increased measure of protection.
That's the theory. In practice, after 4 years of use on the boat, I have not had any failures in the built in system. No component has failed, yet. When underway, I normally play music
from mp3's stored on the machine. I have been in some rough water
and it has not effected the machine. I do have a catamaran
and don't heel, so I can't speak to whether the attitude of the drive while running will have any effect.
You mean that DC-DC power supply I have not installed yet? Okay, okay, maybe this weekend!
There are several manufactures that make PC's and power supplies that are suitable for automotive use. They have smaller form factor boards and make power supplies designed to operate from the electrical system
found in cars. Typically, the main power supply is through an unswitched circuit and a sense circuit is attached to the ignition/ACC setting. This allows the machine to be brought down gracefully when you turn off the car. The supplies typically have a voltage sense that will shut down the computer when the system voltage gets too low. This keeps you from killing your batteries. They also tend to have delay circuits so that when you get an under-voltage condition during engine
start, you don't have system resets. They typically are lower wattage than the AC-DC supplies. This is due to the efficiency associated with not having to rectify and regulate the input voltages. For the lower wattage supplies, they don't even have cooling
fans! No wasted energy on producing heat. They have supplies that can be used from 6 to 30 volts. Just about perfect for a boat!
There are three issues I am hoping to resolve. The first issue was major for me. When I go from shore power
power, my AC systems get momentarily interupted. I can't tell you the number of times I did this with the machine running (gotta have my tunes!). This would reset my machine, not the best thing to have happen. To rectify this, I put in a UPS. These are heavy and result in more complexity, another thing to break and have some energy loss. I even observed some power usage when the computer was not on! Not the best thing when cruising. This
The second issue was one of power usage. The computer, and because I had to go through the inverter, plus UPS, then the battery
uses more power than it could. Not the best thing for a cruiser. So, eliminating some components, more reliable system!
The third was heat. My power supply has two fans in it to get rid of the heat. Heat is wasted energy, unless of course it is winter! I had too much heat build up in the cabinet I have the computer installed. This results in my having to remove the cabinet door and exposing all the mess in there. Okay, so I don't mind it so much, but it is not a statement of good esthetic's. I thought going to a DC-DC power solution would help that also. I suspect however that water cooling
will have a greater effect. Please note however, I am not certain I'd recommend the water cooling route
to anyone else who is not a computer hobbyist. It just seemed like a cool thing to do! (please don't yell at me for the pun!) I like messing around with computer probably a little bit more than I like messing around with boats (Is that possible!? Blasphemy!)
Lots of additional info available. Search on "car pc power supply" or carpc.