Okay, I'm typing this from my family computer because my own one is braindead. I have Windows 2000.
This is what happened:
1st boot: Shows my desktop and mouse cursor but nothing else loads. So, I reboot...
2nd boot: Blue screen shows up as Windows is loading and says to reboot and if the screen comes up again I should do certain things. So, I reboot again...
3rd boot: IDE devices couldn't be recognized. I had to reboot a few times before they were recognized...
Then, a Windows screen comes up saying its recommended that it scan my drives for errors. It has 3 stages. First stage, it found some errors or something. 2nd stage, it fixed errors. 3rd stage, it recovered lost data.
Now, everytime I boot it goes to the windows 2000 loading screen with the big graphic of Microsoft Windows 2000. About 1/2 way through the loading the screen flickers and gets a little distorted, I have never noticed this before. Then, it goes to a black screen and restarts my computer.
Now, it's just an endless loop of my PC restarting over and over.
Hmmm either corrupt windows install or hardware problem. From your last remark, could be either be a shot harddrive or mobo. Memtest may help find fault for RAM issues can verywell cause this. If it does, swap out the ram and put into differerent slots find if its a ram module and/or slot on the mobo. My money is on that mobo.
Mobile Barton 2500+ @ 2420mhz 11x220 1.7v
Asus A7N8X Dlx 440 FSB
1gb Geil GD pc3500 Dual Channel (2-3-3-6)
Segata 80gb SATA 8.5ms seek
ATI Radeon 9800 Pro to XT(420/730)
Clearly your os is failing. From my experience, nothing will help it for long. You need a full reinstall, but befor you do, consider replacing your hd. It seems that you are getting bad sectors and this will continue until the hd won't work anymore. Pull off anything important while you can, if you can.
As toher said It can be quite a few thing. Mostly HD, PSU, or memory. ID be leaning more towards HD or PSU. Specially if your bluescrean was unmountable volume than your bios cant detect your hd...HAppened to me last week one of my HD in my Raid0 died. Everything worked fine than rebooted straight into a bluescrean. Some data got corrupted had to remove the faulty drive and reisntall...
If your not quite sure or experience take it to a pro like phoenix said...For 60$ youll know whats wrong.
Since you have another comp...before I paid to have the broken one bench tested I would switch out power sources just to eliminate that as a problem. If, by chance, that is the problem you can spend the money on a new power supply instead of a bench test.
I am a novice with computers. When something is broken (anything) I have learned to do the simplest thing first.
Another point is how critical is your data? If you loose that comp is it going to be a big deal? If that is the case and your comp is on an endless restart loop I would take it somewhere and retrieve the data before I messed with it any more. Assuming of course, you can't get it going and get your data off like the previous poster suggested.
I had a comp that was doing wacky things like randomly restarting and so forth as well as simular problems to yours. It turned out the power source/mobo plug had actually melted a bit. Presumably it started out as a power source problem but then became a mobo problem because of the scorched/fried plug in.
Have you tried turning the power source off and back on at the back? I wonder if clearing cmos could possibly help? Could that data have gotten "corrupted" in the process of all this other happening? Is that even a possibility, guys?
If you suspect the power supply, I wouldn't keep turning it on and off too much. It might pop and fry something else. If you switch out the power source make sure you ground yourself by touching something metal like the unpainted case frame and discharge that static electricity before you mess around inside the computer.