Not necessarily in this order -
1. connect it to an external monitor and see what happens then
2. have her run what she was running when it occurred
3. Clean boot it and see if it still produces the fault condition
4. I cannot reconcile the apparent faults to interference but check what other equipment she has running when the error occurs if it does
Even when not connected to the AC supply there is a chance that stray EMI could be picked up by circuits in the laptop.
5. Any chance cooling fan sleeve bearing is shot so that when it gets warm it makes the noise and goes slow
1. connect it to an external monitor and see what happens then
2. have her run what she was running when it occurred
3. Clean boot it and see if it still produces the fault condition
4. I cannot reconcile the apparent faults to interference but check what other equipment she has running when the error occurs if it does
Even when not connected to the AC supply there is a chance that stray EMI could be picked up by circuits in the laptop.
5. Any chance cooling fan sleeve bearing is shot so that when it gets warm it makes the noise and goes slow