Computer troubleshooting advice/opinions wanted.

[Rich]

I've been asked to look at a Windows 7 computer that no longer boots. It is somewhat of a community computer mostly used by none tech savvy elderly persons. Took a quick look today with the original Windows install disc in hand. It has an AMD dual core processor about two years old, and is not overclocked. Going through the BIOS only showed me one (there should be two) hard drive (and the Windows repair function on the install disc only showed a Drive D:). I can get into the start part of Safe Mode, but then it just sits there with an empty screen with a blinking cursor.

Now, I'm of the opinion that the C: hard drive took a hike, or an outside possibility of a bad power supply. This is without opening the case.

Now to my burning question.

Given that that is an AMD computer, could I (for troubleshooting only) substitute the hard drive out of my desktop which has an Intel processor and has Windows XP and Mint 10 on it. I don't expect it to run like the original screen, but could it get to the point where one can say, "yep, that HDD is bad, gotta replace it."

I have a external drive USB harness, but it is in a box somewhere in a storage shed (isn't it always the situation, where the problem you prepare for can never be diagnosed because the correct tool is somehow no longer available.).

[Rich]

Thanks Chris.

I'll be updating my desktop anyhow when I get time, so it's not like I'm losing an active computer.

[mekender]

ok two things are likely happening... If the BIOS is not seeing the C drive, then the drive is likely dead... BUT!!! the machine is trying to boot to safe mode which should not be possible on a dead drive... So My guess is that D has an old install of windows on it and it is trying to boot to that.

Typically a OS load that boots to the windows logo and freezes is a software problem not a hardware problem though.


Now there is another possibility though... if the machine is one that someone built, which is what it sounds like... The C drive could be plugged into a HDD controller that the BIOS cant see.

For example, in my machine I have to use a secondary chipset to run my SSD correctly.

If that is the case, then the problem could lie with the chipset hardware or firmware.

My first attempt at troubleshooting this would be to physically unplug the cables from the second drive and see what happens in the BIOS and in a boot... Then if that failed, I would try a different cable and a different plug on the board for the drive and see if that fixes things.

If after doing that the C drive is not recognized by the BIOS, then I would say it is almost surely dead.

[Yogimus]

Also, fun fact.... when C drive dumps out, D drive becomes the new C

[Greg]

Could be a lot of things. Open the case, check the fans, reseat everything (especially cables)....

Then boot it off a USB stick, do not try to add a new hard drive to a situation you don't yet understand.

[mekender]

Also, fun fact.... when C drive dumps out, D drive becomes the new C

Sigh...

/starts channeling his time as a MS storage SME

Mmmmmm, well drive letters are not assigned by the hardware and are purely a function of the OS so that is partially true. Reallistically, what you see in windows as a "drive letter" is a volume identifier and does not actually signify a physical drive but a logical volume. It is possible to have up to 4 volumes, each appearing as different "drives" in windows on a single physical disk when you format it as NTFS. This is due to the way that volume information is stored in the MFT, there are only 4 spots for the info to be stored. (I have had to step through this information with a hex editor)

In the BIOS, the drives will likely be identifiable by a combination of the drive serial number and its capacity. In many cases capacities are different so this makes identification pretty easy.

But in the case of Windows, if the boot drive dies and then the computer boots to an old version of windows on a different drive, then that boot volume will be called C.

That said, if the boot drive is fine and the computer boots normally, the volume letter structure should stay intact even if physical drives are not recognized by Windows. So for example, you have a boot drive that has a volume called "C" and 4 secondary physical drives with volumes called: E, F, G, H (I have this setup)... If you loose F, then the machine will boot with E, G and H identified as such as expected.

Windows stores letter assignments in the registry hive linked to the GUID of the drive in the registry. A typical install scenario has windows assigning the letters automatically and they are not specified by the user. This means if you force the machine to reidentify volumes, assuming they are auto lettered, the lettering MAY change. This can occur even if the drives are all present as the letter enumeration is done based on the time frame of how the drives are recognized and mounted to the OS. I had to tell a customer more than once that MS has no way to guarantee drive letters. Because of this, a good program will actually identify volumes based on their GUID and not their letter.

/ends channeling

[Greg]

Rich, when they're done waving their thingies, boot it off a usb stick. Any 'live' Linux distro should be fine, I like Knoppix. Definitely better for troubleshooting than a borked, corrupt-to-an-unknown-degree Windows installation.

The system may have viruses, or bad hardware, etc. Don't connect a hard drive you're not prepared to lose, at the very least reformat and possibly even have fried.

[mekender]

Unless your controller initialization order changes, and you are not in AHCI mode.

Right as I hinted at in the next paragraph... I was mainly focusing on typical install configs and AHCI is not normally used unless the person doing it knew to use it.