Hi,

I have an HP M9000t desktop running Vista Ultimate 32 bit. As of today, it has decided not to start up. When the power is turned on, the initial noise that usually goes away once the system loads remains. There are no lights on the keyboard, and the monitor displays a monitor status box stating that there is no input signal and promptly goes to sleep. This happens in a matter of seconds, and nothing else is displayed on the monitor screen. I tried to use the System Recovery disc, but the COMPUTER does not load it either. I can only assume that the hard drive is bad since it won't even run the recovery disc. Any thoughts would be greatly appreciated.Can I ask what the noise is and where is it coming from?I'm assuming the noise is the fan. It's the same usual noise that would always happen once we turned on the computer which would stop once everything booted up. Now, nothing happens and the noise persists.I dont mean to ask silly questions but are there any CD/DVD's in your drive or any USB attachments when you boot up? That includes Sd cards or memory sticks?Nothing in the drives and no attachments other than the printer on USB.Try a different monitor.

When was the last time you blew the DUST out of the computer with a can of compressed air?I took care of the dust buildup very recently. It kept randomly restarting, and once I blew the dust out, that problem diminished, although it would still do that occasionally. I've read that Vista has that issue, so I've learned to live with it.I don't think your hard drive is bad, since you get no image on the screen at all. The sound you mentioned makes me SUSPECT that the power supply needs to be replaced. How familiar are you  with the hardware of computers? Power supplies can be one of the toughest components to install.When we REBOOT our computer many times our hard disk going to rough. Now you can boot with bootable cd.Thank you for your posts.  I've replaced RAM and other cards before, but not the power supply. It does have many CONNECTIONS, and I've bookmarked some specific info for my model on HP's website for replacing the power supply. I'll just have to be patient, careful and see what happens. I'll let you know the results when I'm done.Patience and being careful are the keys so you're already ahead of the game...
Most connections can only go in one way so take it a step at a time...

Let us know.Wait! Before you go pulling out the power supply, open your case and confirm that it is what is making the noise.i know this post is a few weeks old but was wondering if you had solved your problem. i ran across this post while searching for help with my own problem so i thought i'd throw in my 2 cents. if you haven't replaced the power supply and still want to, it's not as complicated as you may think. i've replaced mine twice with no problems other than the first new one i bought died on me in a few days and i had to replace it again. just pay close attention to where everything is connected to. another thing you might want to check if you haven't got it running yet is making sure the power supply is completely plugged into the motherboard. i've had this happen to me before. if you have dropped or had something bang against the computer tower, it's possible the power supply could have become even slightly dislodged from the motherboard. i can't remember for sure if my fan stopped working when that happened but i do know that nothing would come up on my screen. i at least remember that much. hope you're up and running! Before you remove the existing PS, photograph all your connections with a digital camera. Then when you put in the new one, you'll have a visual map of how it all connects.