Computer freezes

[Rdutch]

My Laptop freezes immediately, when I try and install xp it says non system disk, when I run any utility it runs and freezes, I tried magic boot and every program on it runs and freezes. I ran a disk utility to try and format the disk and it worked so the hd is clean, and an error check worked and it checked out fine, but the Hitachi supplied disk software wont even run. I tried switching the memory around and just running with one memory and it works the same every time. I opened up the computer and checked everything, and cleaned all the connections, still the same problem, any idea on where to go from here?
any help will do thankyou
Ray

 

[Rdutch]

Yeah I ran memtest, it freezes when it starts, always at different times but as soon as I start it, it freezes. No Flopy though I ran the cd version. I tried ultimate bootdisk also and every memory program on that fails to start they freeze up, even the other tests. I cleaned the cd lens it seems the cd runs fine because it loads the programs to start but from there it fails. When I try and do an install with xp it starts then fails at different times, sometimes it gives me the ntdlr not found error.
Thanks