-- My PC

Model: HP Pavilion A1487c
Hard drive: Samsung SP2504c (SATA)
OS: Windows XP Media Center 2005

-- Problem:

One day the PC's BIOS could not detect the hard drive anymore, and of course, the PC could not boot anymore either.

I bought a USB-to-SATA adapter, connected the hard drive to the adapter and plugged it into the PC via a USB port, booted Mini Windows XP from a CD, opened Windows Explorer and there was the hard drive, with the file system structure apparently working OK.

So it seems that the HDD's contents are OK, but:
1) The BIOS cannot detect it when it is plugged via a SATA port, and
2) Of course, it won't boot.

On the other hand, I also tried plugging a DVD drive to the same SATA ports I had first connected the HDD to, and it worked. So it looks like the SATA controller and port are working OK, unless they have some trouble with HDDs specifically.

Some people in the internet forums say that this problem is to be fixed starting the recovery console and running FIXMBR. I have two questions about this:

1) What does the MBR have to do with whether the BIOS can detect the HDD or not? I'm asking because I really have no idea how the BIOS detects the drive, but I thought the MBR only had to do with the drive's booting capability. That is, I understand that the MBR has to do with the OS, so if the drive has no OS then it has no MBR; and even then, the BIOS should detect it. Please correct me if I'm wrong. I repeat I am no expert at this.

2) Even if running FIXMBR were the solution, there's another problem. As I said, I have a Media Center version of the OS. I understand that if I run the FIXMBR command, that might fix the BIOS detection and the "bootability" problems, but I'd lose the Media Center feature. Is there a way to get the drive back working as a SATA drive, booting the OS and keeping the Media Center feature working?

Thank you very much!

[Insert usual warning about risks of DIY here. Assuming you accept the responsibility that you could make things worse or even totally unrecoverable, then...]

You are correct to be suspicious about the advice you received. The MBR has nothing to do with BIOS disk reporting (or lack thereof).

I can guess about some possible explanations of the behaviour you report, but further diagnosis is needed IMHO. In your case, I would start by checking that the Samsung drive spins-up immediately & stays spinning, when attached via the PC's SATA & power (but is then not reported by the BIOS). There are several possible troubleshooting approaches, and other readers may suggest different ones.

P.S. Before doing any of the above, then if you accept the risks of DIY, you should consider copying all important data off the Samsung disk ASAP (when it is recognised via USB), to another disk, in case the Samsung disk dies at any point.

Vulcan:

Thanks for your reply!

I think I already checked whether the "Samsung drive spins-up immediately & stays spinning, when attached via the PC's SATA & power"; I think it started spinning, but then it stopped after a few seconds. I'm not sure right now, cause I did it a couple of weeks ago. I will try it again in the weekend.

I have already backed up all important information, so that wouldn't be an issue. However, I'd like to get the HDD back working, for a few reasons:

1) A new HDD costs money.
2) I assume that if the contents can be accessed via a USB connection, then the HDD is OK. Am I wrong to assume this?
3) As I said, my PC has an OEM version of Windows XP with Media Center, and I understand I'll lose it if I change the HDD.

Thanks again for taking the time to read about my problem and replying!

Thanks for the update.


OK, I'll be interested in the result. The reason for the question is related to the PC's power supply to the drive. One possible reason for the drive working when attached via USB & therefore using an external PSU, is that the PC's internal +12V supply to the drive could be out-of-spec, and only drives (and some fans) use +12V in a typical PC, so the PC may appear to work OK, even with +12V out-of-spec.

Do you have any other SATA drives (spare or in-use)? If so, and if you are prepared to take a risk, you could move one to use the same power & SATA connections as the Samsung drive, and see if that drive is recognised by the BIOS (although this isn't a conclusive test).

[Edited to add: If the Samsung drive does indeed stop spinning when using the PC's internal power, as you think you remember, but works OK using external power from the USB adapter, that is a potential indication of a problem with the PC's power supply to the drive.]


Wrong assumption IMHO The drive may be OK, yes, but I can think of a couple of drive failure mechanisms, that would cause the drive to work via USB, yet not be recognised by the BIOS. Therefore personally I'm not assuming that the drive is OK.


I stopped doing Windows sys admin some years ago. You'll need to find a Windows support forum if you want to ask someone about that. For what it's worth (which isn't much!) my recollection is that even the OEM WinXP versions did allow an HDD to be changed, without needing to be re-authenticated, if that is the only component which changed - but I could be wrong.

If you have a spare disk, at least as big as the Samsung, you could test this by cloning the Samsung onto that spare disk temporarily (don't boot Windows with them both installed at the same time!), and see if Windows complains when booted from the other disk.