G73 - is it possible GPU high temps to be caused by a sudden software or firmware glitch (not by dust/paste)

My G73JH was repasted 3.5 years ago and I've never had a heating problem since. I've also never installed or uninstalled any drivers or programs that have to do with graphics or power management since the time my GPU was repasted. I'm still on Bios 209. If it ain't broke don't fix it. Basically I haven't done anything to cause a very sudden increase in GPU temps (around 77° idle, 105° in the first 5 minutes of loading up Skyrim). The only incident that comes to my mind is when another game crashed on me while I was trying to alt-tab from it. It's a retro pixel looking game with very low resolution, so when i alt-tabbed from it, my Win7 desktop res was screwed up for a moment, then I think I had to restart. After that, the high temps and excessive fan noise started. Before that - no excessive fan noise, nothing. Now even when I open Facebook in my browser the fans rev up and the temp goes up to 80°, I don't know if a crash and messed up desktop resolution can cause something to glitch in my operating system or my Bios or somehow switch my graphics card to a permanent overdrive, but maybe it is possible? At first I thought it might be some kind of virus, but I scanned my drives with 2 different antivirus/malware programs and found nothing. Also, at 80° the air vents blow out relatively cool air with just a bit of heat from the vent that's on the side of the power button. I used a compressed air can to clear the vents, then opened up the bottom panel and cleared out all the dust i could, still no change in temps.
Seems to me, if this is strictly a GPU fan dust build-up (where i can't reach with the compressed air) or thermal paste dry-up, it wouldn't start so suddenly… i mean, i would've heard the fans gradually making more and more noise, not just suddenly one day making a lot of noise. I mean, I'm used to the fan noise for 3,5 years now, i can detect slight changes in it, and I didn't notice any change until after that game crash.
So, before I go ahead and take apart the whole laptop to clean/repaste the GPU, I want to be sure that this cannot be caused by a reason other than extremely sudden dust build-up or paste malfunction. What do you guys think?

 

If you're having high temps, high fan noise, and cool air blowing out, that typically means the heatsinks are not in contact or seated properly. It should be blowing out warm air, to get rid of the warm air. Your best bet would be to do a repaste of the thermal compound and doing so will also make sure the heatsinks are seated properly.

 

A small knock can do it if the paste job was not 100% or a faulty heat pipe.