set from the bios setting frist boot divice hard disk set from the bios setting frist boot divice hard disk

I would add that it is more likely that the 12 volts on your power supply is still operational giving power to your system fans and possibly your CPU fan also, allowing you to think the processor is still good. It may be and only one or several of the other voltages from the power supply is deficient causing failure of the motherboard and the processor to operate as they should. So before anything else, check your Power Supply to verify that it is producing necessary voltages to power your system.... Assumptions cause problems for everyone. Generally speaking CPUs only rarely go bad and could still be good even if the motherboard, power supply, hard drive, and CD/DVD have been exposed to conditions that disable them completely. Be aware that placing a bad motherboard or power supply into another system for troubleshooting reasons could and sometimes does incapcitate the troubleshooting system. It is also possible for a shorted CD/DVD or floppy drive to create a system that does not boot. So the best thing to do is disconnect all peripherials from the motherboard and the power supply. By peripherials, I mean the CD/DVD, floppy, hard drive, all usb devices, and the monitor from the computer. Don't be afraid to use a different mouse and keyboard if you think it might be necessary. The likelihood of a mouse or keyboard causing this kind of issue is very low but not impossible as I've seen keyboards do some very strange things. Once you done as much as you can do to reduce the # of possible causes, turn the computer back on and see what happens. If the problem lies with one of the peripherials, then you should hear a bios beep at a minimum. Once you hear that bios beep, plug your monitor back into your system and check to see if you have a display and you probably will have assuming Power supply, motherboard, and cpu are good. But if you have no beeps and no display in this limited scenerio, then a best guess would indicate either a faulty power supply or motherboard. As I stated previously CPUs only rarely go bad unless a fan has gone bad allowing the CPU to overheat. On most modern motherboards CPUs are protected by a circuit that prevents CPUs from overheating due to a faulty fan, however I cannot assume to much since I can't see your configuration..
Hope this helps and it is what I should have stated to begin with, but when you mentioned categorically that your CPU was good, it pulled me off into the tangent of asking why you believed that. In the old days, it was much more difficult to assume the status of a CPU.


I would add that it is more likely that the 12 volts on your power supply is still operational giving power to your system fans and possibly your CPU fan also, allowing you to think the processor is still good. It may be and only one or several of the other voltages from the power supply is deficient causing failure of the motherboard and the processor to operate as they should. So before anything else, check your Power Supply to verify that it is producing necessary voltages to power your system.... Assumptions cause problems for everyone. Generally speaking CPUs only rarely go bad and could still be good even if the motherboard, power supply, hard drive, and CD/DVD have been exposed to conditions that disable them completely. Be aware that placing a bad motherboard or power supply into another system for troubleshooting reasons could and sometimes does incapcitate the troubleshooting system. It is also possible for a shorted CD/DVD or floppy drive to create a system that does not boot. So the best thing to do is disconnect all peripherials from the motherboard and the power supply. By peripherials, I mean the CD/DVD, floppy, hard drive, all usb devices, and the monitor from the computer. Don't be afraid to use a different mouse and keyboard if you think it might be necessary. The likelihood of a mouse or keyboard causing this kind of issue is very low but not impossible as I've seen keyboards do some very strange things. Once you done as much as you can do to reduce the # of possible causes, turn the computer back on and see what happens. If the problem lies with one of the peripherials, then you should hear a bios beep at a minimum. Once you hear that bios beep, plug your monitor back into your system and check to see if you have a display and you probably will have assuming Power supply, motherboard, and cpu are good. But if you have no beeps and no display in this limited scenerio, then a best guess would indicate either a faulty power supply or motherboard. As I stated previously CPUs only rarely go bad unless a fan has gone bad allowing the CPU to overheat. On most modern motherboards CPUs are protected by a circuit that prevents CPUs from overheating due to a faulty fan, however I cannot assume to much since I can't see your configuration..
Hope this helps and it is what I should have stated to begin with, but when you mentioned categorically that your CPU was good, it pulled me off into the tangent of asking why you believed that. In the old days, it was much more difficult to assume the status of a CPU.