Internal heat

[eggthief]

Ok so I did nothing to my hardware for a long time, but today when I launched a game, I suddenly got booted back to my desktop with a message that my GPU stopped responding and that the settings were set to the minimum. I immediately checked my catalyst control center and to my big surprise I saw that my GPU had a temperature of 81 C degrees, which pretty much explained why I smelled the inside of my PC while gaming.

Anyway, I turned off the auto pilot of CCC and reset the settings to factory default while setting fan speed to the maximum, but this still doesn't cut it while gaming and even now while not gaming at all it is 65C (normally being 54C) at least. So I opened the computer and I saw that the only running fans were the one attached to the main cooler and the GPU fan. My Motherboard was replaced a couple of months ago by a local pc shop so I had no idea of this as I haven't opened my case since.

Anyway, I saw why they didn't attach the two extra fans who are currently unused, the new motherboard has only one, blocked out of sight due to my GPU, input spot. Eventually I managed to place one of the two fans into the spot, but when I booted my pc again, it only ran for about half a second. So what I'd like to know is:

1: What could have caused the sudden increase of temperature in my PC? Note that the two extra unused fans had nothing to do with it, I've ran the system without problems this way for a couple of months now.

2: How come when I tried to attach one of the extra fans to my motherboard, it simply didn't work? The input spot says "System Fan".

Anyway here are the specs of my GPU and Mobo:

GPU: Ati 4870 520mb
Mobo:Gigabyte G31

[newt]

It sounds like your power supply isn't enough to handle it or is dying, which could also explain the fan not working. 81 C isn't enough to make it stop working. Max temps for those cards is in the 90's. What wattage is your PSU?

As for the temp spike, it could just be dirt. Take out the card and clean it with compressed air