Ok, you mentioned you cleaned it a few days ago - what's your definition of clean?
My definition is a little anal I suppose, but i'd remove the GFX card from the PC, remove the Heatsink and Fan, clean off any TIM, use an air compressor to clean the Heatsink after removing the fans, then clean the fan blades with Plastic safe solvent, blow the dust out of the fan motor and/or oil if it's that sort of fan.
The fans are usually just attached to a PWM header on the card, if you want to see how they are going after you clean them, just plug them into a PWM header on the mobo, plug your screen into the onboard GFX port, jump in the BIOS and using the PWM controls throttle them up and down to see if they are balanced and running nicely again (alternately you could boot to Windows and use something like Fan Expert, but you'll have to install GFX drivers and may have driver issues once you put the main card back in later).
Once you are satisfied the fans are running nice and smooth again or you have replaced them with new ones if they were fatally damaged, reattach them to the Heatsink, apply some TIM and reattach to the GFX card and put it back in the system.
Job done properly - you'll get twice as much life out of your components if you clean them thoroughly at least once or twice a year.