Have a Sony Laptop, P4 2.6 running Win XP Home w/512 Ram. Laptop will start running slow then just comp0letely shut down. Try to run Norton AV and half way thru scan it will just shut down. Same when trying to run Adaware. There seems to be about 62 processes running. Can not keep this running to do full scans to find out the problem. When trying to go into safe mode it stops responding after the screen showing the drives strating up,

Any suggestions on what I can look at?

The machine is used for autocad working with file sizes of 3500k.

Thanks,

Joe