CPU fan slowing/stopping randomly during games?

[pcgamer420]

Ok I have a major problem on my hands. I upgraded my rig a couple months ago Installed a P6T Deluxe v2, i7 920 overclocked to 4.0, cooled by a Prolimatech Megahalems heatsink with a NB Multiframe s-series M12-P fan. Works great most of the time, but every once in a while when my CPU is really working hard (1+ hour of playing video games such as Cryostasis, The Witcher) the NB CPU fan stops working. It doesnt completely stop, it just slows to a crawl and next thing I know RealTemp shows 90-100C temps and my heatsink is hot to the touch at which point I immediately cut the power off to my comp.

First of all is my CPU now damaged because it has been as high as 90-100C for as long as a few minutes at a time? This has now happened twice. Today after it just happened again while I had played Witcher for ~3 hours, I put a scythe 120mm case fan on top of the megahalems to create a push/pull and better vent the heat. I'm hoping this could help better prevent the extreme temps in case the CPU fan fails again but I really am wondering what the problem could be?

I'm new to hardware troubleshooting and so I'm not sure if this is a fan, PSU or motherboard issue, does anyone have any advice for me?

 

[Kato1144]

is your fan connected to the MOBD or PSU directly?

and for the 90-100 for say 2-3 mins at a time might, just might cause some thermal wearing shorting the life expectancy a bit for sure and might not overclock as well after exposed to the xtream temps so you should probably run some stability test when you are sure you fix this little problem.

As for advice try changing out the fan, or the fans power source, and do the testing on stock speeds you don't want a third 100oC incident.

BTW can you post a link of your cooler and fan.

-Kato