If its one thing i've learned over the years with computers is backup backup backup! After having installed and configured your carputer to your liking it is a good idea to clone the hard drive. Should anything happen to the drive installed, you can swap it out with the clone. It is also a good idea to keep your media on a seperate hard drive.
Of course you could pay a little bit more for a hard drive with an accelerometer feature built in:
http://www.amazon.com/gp/product/B00...&tag=attgig-20 5 year warranty to boot!
As it has been mentioned already, hard drives are alot less susceptible to shock than they used to be. Heat is still an issue.
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