The 160 gb is not gigabyte in the common sense, but 160 000 000 000 bytes, which is 149 real gigabyte (by multiplying by 1024 three times). This is the case with all the harddrives you can buy.
There is nothing wrong here, and its not the fault of vista.
HP was indeed telling you something wrong.
It is true that additional space is used for "crash protection" if you want to call it that. Some space is used for recovery files. Every time you change something mayor on your system (installing/changing drivers or software) a backup is made, so if your system does not work well anymore you can recover to the old state that was running smoothly.
You can configure how much data (at a maximum) is used for this backup information. Which gives you a bit more space for your own data, but reduces the amount of backup data (so if you reduce this amount, some backup points made in the past will be lost).
Hope this helps!
Recently bought a new HP Pavillion notebook. Bought a 160 GB drive with it, instead of standard 80 GB.
Drive came partitioned into two partitions:
C drive of 142.6 GB (+- on the point part)
D drive of 6.4 GB as recovery drive.
That adds up to about 149 GB, not 160 GB
I"m not found of the recovery drive but I think I'm stuck with it.
Called HP tech support (twice), and was told that the roughly 11 GB of missing drive space is being used by Vista for system crash protection. First tech had really bad English tried to sell me an external hard drive. Second tech didn't speak really good English either, so not sure he understood. Both babbled on about the recovery portion of the hard drive.
Was HP blowing smoke? Did they short me by 11 GB of capicity? Or is that normal and the tech couldn't explain what was actually happening?

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