During the three years you've owned this laptop, has the cooling system been cleaned out?
When the cooling system is dirty, the cooling capacity drops tremendously.
Once the Processor overheats it is turned off. (BIOS turns it off)
The Air Intake Duct is on the bottom of the laptop. A prime area for ingesting all kinds of foreign materials.
Dust, dirt, hair, food crumbs, carpet deodorizer, etc.
AC adapter (Charger) removed, Battery removed, a can of compressed air for computers may help alleviate the problem. (There is a CORRECT procedure for doing this. Please ask before you attempt it. Post in a Comment. Believe upper right of your page)
Problem is, that the above mentioned foreign materials, may have congested in an area inside the laptop, that only a tech can remove.
The laptop is opened up so the tech can physically use a soft brush, Q-tips, pick, and a can of compressed air, to remove the packed 'crud'.
The following is just for edification purposes, and not an invite to do the procedure yourself. However, if you feel inclined, I will guide you the best that I can over the internet, in this forum.
I would like you to download the Service Manual, for the Acer Aspire 9300 Series of laptops. (FREE)http://www.tim.id.au/blog/tims-laptop-service-manuals/#toc-acer
On this page scroll down to the heading - Acer, subheading Acer Aspire.
The second Aspire heading down that starts with
Aspire 1200, 1300, 1310, etc.
Go to the 8th line down, and scroll over to - 9300
Left-click on 9300.
This is a PDF file. It may take up to 30 seconds before you see the first page. (Took 12 seconds before I saw the first page just now)
Let the file fully download before looking through it.
(An additional 28 seconds for me)
File should download to your My Documents folder. (WinXP - Start>My Documents. Documents for Vista)
It may go to a subfolder of My Documents. Downloads.
Or it may go directly to your desktop screen.
Depends on where you have your downloads, set to download to
Double-click on the file name. (Aspire 9300 7000 Travelmate 7510.pdf)
Base view (Bottom of the laptop) is shown on Page 17. Shows the Air Intake Duct. (Number 2 -Cooling Fan)
Page 78 shows the System Fan, (Cooling fan), and it's surrounding shroud.
Inside that plastic shroud is where the foreign materials collect, and a can of compressed air from the outside of the laptop, may not be able to dislodge it.
It could be also that the Thermal paste has dried up.
Processors run pretty warm, but an AMD processor runs Real warm. (Actually could be considered Hot)
The heat can eventually dry up the Thermal paste.
In-between the top of the Processor's case, and the bottom of the Heatsink, thermal paste (compound) is used.
The top of a Processor's case, and the bottom of a Heatsink are not perfectly smooth.
A microscopic view will reveal 'Pits, Hills, and Valleys'.
These create air pockets.
Air is an Insulator, and not a Conductor.
The Heatsink conducts heat away from the Processor. (And the fan's air flow takes heat away from the Heatsink)
Thermal paste is used to fill these voids.
(The Heatsink Module is shown on Paqe 80 in the top photo. The top of the Processor's case is also shown on Page 80, in the two bottom photos)
The top of the Processor's case, and the bottom of the Heatsink, should be THOROUGHLY cleaned, and new, fresh thermal paste used.
It is also a good suggestion to use some form of cooling pad underneath the laptop. Most use fans, and are either Battery powered, or powered by plugging into one of the laptop's USB ports.
Barring that cleaning the laptop's cooling system, and replacing the thermal paste does not cure the problem, then I suggest there is a problem with the GPU.
Graphics Processing Unit.
For the Acer Aspire 9300 Series of laptop's, the GPU is Integrated.
Soldered directly to the motherboard.
A GPU is an Integrated Circuit. Slang term for I.C., or Integrated Circuit is 'Chip', or 'Chipset'.
At the bottom of the chip are contact pins. These pins fit into a special socket on the motherboard.
(Just one type of surface mount socket that may be used,http://en.wikipedia.org/wiki/Ball_grid_array
On some laptops there has been an occurring problem, where the GPU has become hot, and lifted up out of it's socket. The solder joints melted enough to let the GPU lift up.
Lets the contact pins come up out of the socket.
This problem has to be fixed by a pro.
(A REAL pro, and not Geeks Are Us 'techs', if you catch my drift. They'll just want to replace the entire motherboard. 'Parts Changers')