I know my way around computers, but I'm new to the issue of cooling. I'm running a P4 2.93 GHz on an Intel D945PSN motherboard. Until two days ago, my cooling "system" consisted of the PSU and the heatsink/fan that came with the CPU. Within the past week, I started to receive warnings that the temperature was a bit high (60-63C). I have since installed a Silverstone FN121 120mm case fan directly below the PSU. With this new fan, the temperature dropped by no more than 2-3C. I went into TigerDirect and talked to a fellow there who strongly suggested replacing the stock heatsink/fan with a better model. I have now installed a Cooler Master Hyper TX. The difference in sound is unbelievable, but the temperature is still a bit too high (I think) and I'm getting warnings from time to time that the fan is either stopped or very slow. While using the computer (although, not under 'full load' conditions), the temperature has stayed around 58-60C and the fan has been about 300 RPM. At approaching a 'full load', the temperature was 63-65C and the fan was around 1300RPM. Right now, with the computer virtually idle except for my having VNC'd in from work, the temperature is 52C and the fan is at 100RPM. I have no knowledge of this, but I'm assuming that the fan works as fast as it thinks it needs to get to the desired temperature. So, should I be concerned about the fan speed? If no, does that mean the temperature is actually ok? I think I'm going to add an 80mm intake fan on the front of the case but, since the 120mm fan didn't make much difference, I'm not sure how much an 80mm will help. Still, I keep getting these warnings and I'm not sure what to do next. Any suggestions will be gratefully received.