[Darthtanion]

Any of the standard cooling fans made for computers will suffice. The higher the fan speed the higher the airflow it produces... AND the more noise it creates. You'll have to decide what works best for your needs. Since you are having issues, I would probably go with either a 90mm or 120mm fan. Unless you already have a window built into the side panel, you will be ebst served with non-LED type fans. You'll also want a dremel tool as Kheldar mentioned above. This will allow you to cut your holes in the top and side panel for the fan to mount to. I would also recommend some sort of filter material since this will help keep a lot of the dust and dirt from inside your case. They will need cleaning from time to time, but I like the ability to keep the dirt on the outside of my systems. As far as mounting the fans, you will need to drill four holes that match up with the holes on the fan. Either small nuts and bolts or plastic push pins will work for this and give you a stable platform for the fan to work from.