zx5000, model zx5180 3ghz, 512mb ram, 80gig hdd. Works great when it works. I had to remove the plastic case thats around the CPU, and i have to hold the laptop completely vertical for it to work, at any point in time if move the laptop more than say 10 degrees back or forward from completely vertical it freezes and wont work. I thought at first it was a heating issue, and then thought it was a hdd issue, since that have a flaky connection system for the HDD. but testing out some stuff with both of those seemed to not do much change. Called up HP and did the chat support, they think it might be something with the main board. but im just not sure. I'm stumped 100%. warranty is void and its 289$US for me to send it in. Its not software, bios is completely updated. Any ideas?

obviously something is loose (more than likely your CPU since you removed a case cover). I say reseat your HD and your CPU with the case.

the case cover does not affect the cpu placement. And i have reseated the CPU and HDD along with the mainboard 3 times. Each time it does not affect the system at all.