Can anybody please help me figure this out. 2 fans on my Mac Pro are permanently stuck spinning at around their top speeds from the time the mac is turned on, until the time it is turned off or put to sleep Here are the speeds the fans are spinning (according to iStat & smcfancontrol): CPU Fan - 2781 rpm PCIe/HDD Fan - 499 rpm Rear Fan - 2813 rpm Power Supply Fan - 599 rpm Here are the temperatures the machine is registering (according to iStat): HD1 - 32*c/90*f HD2 - 32*c/90*f HD3 - 42*c/108*f HD4 - 41*c/106*f CPU A - 24*c/74*f CPU B - 25*c/76*f Ambient - 21*c/70*f Expansion Slot - 24*c/77*f Here is the computer usage with just Firefox running (according to iStat & activity monitor): *please note that this problem is here no matter which, if any, applications are running User - between 6% and 20%, usually around 10% System - between 1% and 10% Nice - 0% Idle - between 70% and 93% Here is a summary of my machine: Model Name: Mac Pro Model Identifier: MacPro1,1 Processor Name: Dual-Core Intel Xeon Processor Speed: 2.66 GHz Number Of Processors: 2 Total Number Of Cores: 4 L2 Cache (per processor): 4 MB Memory: 4 GB Bus Speed: 1.33 GHz Boot ROM Version: MP11.005C.B08 SMC Version (system): 1.7f10 Serial Number (system): G87171J6UQ2 Problems: Fans are extremely loud! I can't think. I'm a musician; recording is out of the question with this problem happening. Fans are going to eventually wear out, going constantly at these speeds. Solutions I've tried, none have worked. All were done after the problem already existed: Firmware is up to date Machine has been thoroughly cleaned to the best of my ability. There is almost no dust anywhere i can see. Machine has been visually inspected to the best of my ability. I can not find any wires, plugs, etc. that looked damaged, disconnected, etc. I have removed all harddrives and booted up from a known clean Mac OS. I have tried different, known good, video cards. I have reset the SMC from every possible method. I have reset the PRAM. I have tried different optical drives. I have tried smcfancontroll application, iStat, & fancontrol. These have all helped in monitoring the problem but none have been able to fix it. Additional conditions: There is plenty of good airflow around my whole workstation. The air temp around my workstation is always controlled and cool. I only have hardwood floors. This cuts down on the dust created by carpets. I bought this computer about three weeks ago. This problem started about two weeks ago. I have no idea what could have triggered this. There is currently no warranty on the machine. This computer was a very big purchase for me and I have almost no budget to take this machine in for professional repair. Please, please, please send me any ideas if you can think of them. I will greatly appreciate it. I am really stuck here.