Types
There are three or so types of the dv6000/dv9000 series. In each of the two series, there is an AMD type (nVidia chipset), an older Intel (Socket M, 945 chipset) type, and a newer Intel (Socket P, 965 chipset) type.
Common Problems
- In the case of the dv9000: hinges seizing, breaking the LCD assembly apart (see here for a picture)
- Graphics chip solder cracking, causing the computer to no longer render graphics properly, or preventing it from booting up altogether
- In the case of the older Intel versions, they are limited to 32-bit memory addressing.
Solutions
- For hinges, there is no known prevention, only cure: replacing the entire LCD assembly. I find that some units fall victim to this, while others never do, so replacing the LCD assembly is a fairly foolproof way of solving the issue.
- As far as solder issues go, I threat these the same way I would any other laptop: heat the chip to the point of melting the solder beneath it, and then let it cool.
Media
The HP Pavilion dv9000. 
Failed hinges.