Today when I started up my computer, the power button lit up and all the fans came on but the computer would not boot up. The screen kept flashing no signal and the fans kept going at full speed. Normally on startup the fans com on high speed for only a moment then slow down to a whisper, then the COMP beeps as it starts booting up. This time there was no beep, and the fans were going nuts, I seriously thought the fans were going to burn themselves out. I have never had this happen before. Can anyone tell me what may be happening.

I took the side panel off and everything is dust free. The fans are not clogged and none on the heatsinks are clogged with dust. The connection of the dvi cable is secure and the video card is opperating because that fan is on too. I checked everything I could THINK of. 

Please helpThe first thinh you could try is  to reseat your memory module/s by taking it/them out and placing it/them in another slot. Take off also your graphic card if you have any when removing the memory.

This is the first step in finding a solution to this difficult PROBLEM  I swapped the memory and EVEN put the oem vid card back in and it still won't work. I was wondering, considering the comp is 5 years old, do you think the clock battery may be dead and if so would that cause this to happen?5 years old, it is possible that the battery might have drained completely... and mess up your configuration.generally speaking this cell's lifetime is 2-3 years.. well you could change the older one with a new..its rather cheap..look for  a "CR2032" its the name of that button cell..well then you will have to adjust your time settings in the bios and other re-create your previous configuration that was stored in cmos.

Also the noise  your power supply is making..it is near to pass away..so better change this one too  look for one with the same wattage as yoursWell bad news. I replaced the battery and being an electrician, I tested the power supply and it was fine. The only thing that leaves is the motherboard. I took it to a friend of mine who is a comp tech and he told me the board is done. Bottom line it is cheaper and better for me to just buy a new comp. Hp sourced my motherboard for $300 and I just laughed at them and said no. Oh well. Now to decide what new comp I want. Everyone seems to be building their own machines because most prebult comps built by companies like Dell and HP are *censored*. And don't even get me started with APPLE and their overpriced comps.