Strange Laptop Freezing

[RRunner]

I wasn't sure where to post this... hope this is ok.

I am having a problem with an HP laptop that someone has asked me to take a look at. It is an ok machine for what they want to do with it (Celron 1.6 Ghz with 1 Gb ram). The HD was dead so I put in an old one that I had kicking around.

While trying to re-OS it I ran into a strange problem. The machine would freeze periodically. I noticed that there was a lot of flex in the chassis (a lot of missing screws) and when I moved it, the laptop would suddenly un-freeze and continue as if nothing had happened! Any type of physical contact with the laptop seems to cause it to freeze and a slight lift or twist of the chassis will un-freeze it as if nothing had happened. Weird.

Note that if I type on the keyboard while it is frozen, the letters I type show up after I give it a twist and it un-freezes! If I move the mouse when it is frozen, the cursor is moved instantly to the new location (relative to the mouse movement) after I give it a twist and it un-freezes. So very weird.

Before I rip this thing all apart looking for loose connections, etc... does anyone have any ideas where I should start looking? I find it really odd that there could be a loose connection or grounding problem that would freeze the machine (mouse doesn't even move) and given a slight twist, it resumes function without crashing!

[RRunner]

@AmigaHeretic: That is EXACTLY what I am experiencing. If you put your hands on the laptop to use it, the thing freezes. In my case, if I lift up on the bottom left corner of the computer (left of the track pad) it will unfreeze. It is just as if you have put the computer into some form of suspended animation. Everything freezes as if time has stopped. I don't understand how that is possible without causing a crash but even the clock stops. So weird. I'm going to tear it apart when I get a chance and see if I can spot anything.

@Lando and koshman: It is definitely not just the screen display freezing. If I am doing something that involves reads / writes from the HD, the HD stops spinning when it freezes then the HD operation picks up right where it left off when it is unfrozen. At first I thought it was just a display problem but further tests quickly ruled that out.

@odin: Nothing happens when it is frozen. The cap lights key doesn't go on/off when frozen but... if it is frozen, and I click the caps key... then unfreeze it... the cap locks goes on/off immediately after it is unfrozen. Looks like the key stroke buffer still functions while it is suspended. Also, if I plug in the network cable, I can see activity (lights blinking) while frozen. The computer is not actively responding to requests while it is frozen though.

@tone007: I agree. I'm going to tear it all down when I get a chance.