How long does the computer stay on before it overheats? (on average)
I would try just updating the BIOS (and no you can't run BIOS updates via wine)
If you can boot into Windows and apply the BIOS upgrade.
If you don't have Windows there are DOS methods and others that are a bit trickier.
How to Flash BIOS
aloya82-- It could possibly be a dust issue. Since it is an older laptop there is a real good chance that there is dust trapped inside. We need to explore all possible problems before we jump to conclusions.