Overheating CPU - Windows

Hi ya all - I have 3 networked PC's running a shop and when ever the weather gets hot 32 degrees Celcius, they all play up and crash. I have tried CPU coolers but that does not seem to help. One of the computers is in an office and I could use dumb terminals connected to a host and air condition the office but that would mean I would need the keyboards x 2 , mouse x 2 , bar code scanners x 2, and monitors x 2 all with extended cables to reach the office. Does anyone have an answer?? Is there a better way than all these cables?? Is there a better way to cool the CPU's??

I live in Victoria Australia...Yes, we do have computers down under.....most of us even have hot & cold running water and even electricity to our homes....it is SOOoooo special

Darren