My laptop is overheating and causing system instability (spontaneous shutdown). I am well aware of the various solutions there are for an overheating laptop, and I've run through them all: verifying it is clear of dust and that the vents aren't blocked, ensure that fans are working and even placing it in an area where air runs smoothly, all to no avail.
I have traced the problem and the source seems to be the processor. Apart from overheating, it presents no erratic behavior, and the hardware does not appear to have suffered permanent damage because of this issue.
Since my laptop was one of the first models to come along with a Core i5 processor, I cannot for the life of me find a Core i5 replacement; besides, it is for the time being beyond my budget.
If the problem is indeed a faulty overheating processor, is underclocking a viable option for my problem? Does it significantly reduce cpu temperature? If so, how much (%) should I underclock it?