Yea, my kid's computer 'won't load the OS - it is win 7.  It asks to repair the OS or load normally. It starts the loading windows page and the little ball just goes round and round.  I tried to reinstall the os from disks but same thing.  What do the experts say - install a new old disk drive and try again?
 
thanks,
 
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That doesn't necessarily mean the drive is dead.
 
Download a bootable disk utility from the HDD manufacturer, like Seagate or Western Digital etc...  If you don't know what it is, just try one either will at least tell you what the drive model number is and you can figure it out from there.  That should help you determine if the drive is really the problem.
 
If the drive shows OK, try MEMTEST (also downloadable as a bootable ISO file)  to check out the memory CPU system.
 
Those two sets of utilities will catch 90% of computer failures.
 
For the other 10%... start yanking extraneous hardware, leave USB stuff unplugged, pull PCI cards and what not.  Swap known good parts... then shoot the thing with the nearest firearm.

Boot the machine to Linux and see how it works?
http://ubuntustudio.org/
 
You can then scan the drive using a tool like this...
http://superuser.com/questions/171195/how-to-check-the-health-of-a-hard-drive
 
Free CD Image from here...
http://memtest.org/
you can use to do a memory test to verify that the memory in the machine is working ok. If there is no memory, or insufficient memory, then you can get lots of weird behavior.
 
Microsoft's page of advice...
http://windows.microsoft.com/en-us/windows-xp/help/setup/how-to-fix-computer-that-will-not-start

Thanks guys.  It seems like a lot of work and I'm old, fat and lazy w/ more money to spend than time left.  But at least my boy liked taking it apart.  Modern father/son time.  I might have taught him a few new words since they seem to make computers today so you have to take the whole #@^&* apart to get to the drives. ;-) 

Most laptops make it easy to get to the drives from the underside. I'm surprised you found it hard.
 
It is true that laptops are pretty tightly packed. I've taken them apart to the last screw and reassembled. Sometimes replacing a screen or a fan can be a challenge.
 
I have a drive adapter like this one...
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=7220658&CatId=3770
Which makes it easy for me to pop out a hard drive from one computer and plug it into another computer. Then you can do what you like to the drive.
 
Windows will not allow you to install to a remote drive (USB connected). Linux will.
 
 
 

It was one of those slim-line desktops.  The hard drive was buried at the bottom - had to take out the cpu fan to get the caddy out.
 
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Hope you were able to get it working AT....I have a set of jewelers screw drivers just for laptop operating which I try to avoid as much as possible. It seems like they always try  to hide a fastener somewhere so you can't find it. like behind a sticker or under a rubber foot.....I don't think they really want you to get into it :)

It was the hard drive.  I made my son re-install the OS disk - he's downloading all the window updates right now.
 
Thanks for all the help guys.  Good ideas, lucky I was able to keep it simple, stupid.  The only way I got it fixed.
 
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