PS3 Need help getting control fan utility on my ps3 that's not modded

[Mark v]

Hello everyone my fat PS3 80GB is overheating and not playing the CDs that are put in it I opened it up and cleaned all the dust out of every part of it but I also need to put some thermal paste on it which I don't have at the moment so I look into it and decided I want to put a control fan utility on there but how to install it or even get it on the PS3 at all can somebody please help please bear with me I'm not very knowledgeable about the PS3 at all I just bought it used for my kids and they can't even play it thank you to every one willing to help