I have a mac pro 1,1 (upgraded to 2,1) tower 24GB of Ram with with two Quad core INTEL XEON X5355 2.66GHZ processors making 8 CORE. The current Graphics card is a ATI Radeon HD 4870. I am getting kernel panics when I'm working on large audio mixing / editing sessions in pro tools 10. These panics happen after 2 hours or more of work on sessions that are using a lot of cpu and once the mac us running really hot, and the kernel panics show the graphics card is the problem. The graphics card was recently replaced and I am having not other problems usually associated with failing graphics cards such as blue screens scrambling graphics etc. it looks like the graphics hard is overheating when the mac is getting hot and causing the panics. I have seen that is software called Smc Fan control and thinking this will help if I run this when working on large sessions, I'm using os10.6.8 so I wonder if anyone knows which version of that I need to run, and what fans on the mac pro would need to be speeded up to cool graphics card and poss cpu. And also what are good speed settings to use? I'm also wondering about any other methods to cool graphics card and cpu, external fans? Settings that can be changed to graphics?