What causes 360 to freeze?

[fitzybhoy]

My mate is having no end of probs with his 360. The games kept freezing so he replaced the drive. They kept freezing then he got RROD, which he assumed would fix it. He fixed the RROD with a kit from ebay, but the freezing persists. His 360 is dust free inside and is well ventilated.

Any suggestions

 

[woodchin]

The ebay kits aren't much cop, he will be better off using the drilling method.