Dell e1705 Fans not coming on

I have a few year old e1705 on which windows xp went corrupt recently so I installed windows 7 on. But now none of the fans come on and the computer becomes uselessly slow after 15-20 minutes because of thermal throttle. Why would both fans fail to come on and where can I get new ones?

It depends what it is defective fans or mobo failing to start fans. Try updating or reflashing bios. Do fans manage to start after a while when you are in bios setup?

If it just fans that you are looking then probably ebay would be holding the most parts.