So, what uses more power? Laptop DVD player or playing DVD off hard disk?

[Eug]

Has anyone compared power utilization of a laptop 4200 rpm hard drive playing DVD vs. direct from DVD?

It seems to me a great way of watching DVD on the road would simply be to decrypt your own DVDs to the hard drive, so you don't have to take the discs with you, provided you have enough room for a couple of movies. You can erase them when you're done.

I suspect you'd save some power this way, but I'm not sure.

 

[MrMilney]

I'm thinking that playing the DVD from the hard drive would be less expensive in terms of power consumption. My reasoning is as follows: the cost of using the DVD drive comes from the power required to spin the drive's motor and what is needed for the laser itself. The hard drive in your laptop is spinning constantly (or almost anyway) as long as the machine is in use and its heads require less power to operate than the DVD's laser (I believe). Now performance of a laptop hard drive versus a DVD drive is another issue altogether.

Of course, I could be really off here too.