Laptop switching off

That is quite an old machine - I have one myself and I would go with what has been said already re temps. Does the fan run at full speed all the time? and how long since you checked in the air intake aperture and the "radiator" outlet grill.

So you need to first get a very bright light like a LED torch / flashlight shine it into the round air intake and then look into the rad outlet grill if you cannot see a great deal of light then it is probably clogged with dust and crud.
I did this up have a look

CLEANING LAPTOPS

Whatyou can do is to check the air intake aperture and the "rad" and todo that shine a very bright light into the fan aperture and look through fromthe outlet grill
1. You will see if there is a lot of dust in the fan intake and fan blades and2. you will see if the "rad" is blocked in any way when you lookthrough from the outside.

Now to clean you can blow the dust out using compressed air but first make sure youinsert something into the fan blades before you do - to stop the fan fromspinningas spinning the fan with air will cause it to spin at muchhigher revs than it was designed for and can wreck the bearing.
The rad you can use those chenille wire play things to very gently clean therad from outside the machine and again blow the dust out. It is fiddly buteffective.

To see the temps run Speccy Speccy - Download download from piriform and post back the results. We are especially interested in the CPU and motherboard temps.

If you are confident enough I have the instructions on disassembly and the way to clean the machine plus renewing the thermal compound.

Yep I guess the next thing to scrutinise will be the hard drive, the RAM (both are now old specs and in usage) ,andand perhaps the powers source because if either are on their last legs the OPwill have such problems eh?

I have done a few Toshibas including my own over time and they are notgenerally hard to work on and I use a Toshiba specific fix site for what I doand if you are interested it is http://www.irisvista.com/and it is VERY important to thoroughly understand that first page before goingto the disassembly guides as the ribbon cable issue is and can be quite atricky job to perform. Mind you it doesn't list all the models - more the onesthat come here for fixing

As matter of interest it would be handy to know what power settings are onthat machine and it wouldn't be such a bad thing to run these in safe mode

https://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html

https://www.sevenforums.com/tutorials/433-disk-check.html

I also wonder if this is a malware thing too but it can wait till we hear back from the OP.

NB I have to say Torah and Harribo it is a treat to see members who have got their system specs listed as so many times one has to ask posters for them and it gets rather tedious. Both of you are to be commended:)

No mate the fault sounds almost certain it is the temp of the CPU. The problem being that the thermal compound on it and the GPU chip has dried out making any cooling of those chips impossible and the thermal cut out of the CPU shuts down the machine straight away.

See pics it isn't the machine we are discussing but is typical of the set up with the heatsinks in place and with them removed exposing the chips that is where the thermal compound is applied whenever a a laptop (or desktop CPU) is made - or repaired.