That's a hard question to answer with out knowing what software you are putting on it.

Also go to the laptops manufacture site and get the latest BIOS update.plus do you run and have windows update set for automatic updates?

There are alot of different things that can cause a lock up.not enough memory to much running in the back ground,spy and adware a virus.Hardware failure, courrupted sys files,IRQ conflicts,wrong drivers or you may need to update your drivers over heating from dust preventing air flow.might need to defrag the hard drive and run disc cleanup, registry problems lots of different things.