New Dual boot HDD is not getting detected after only one week use

I just bought the 500 GB Seagate SATA HDD for my Dell Optiplex GX 620 system.
I installed XP PRO in C: & Vista in the adjacent partition making it a dual boot system.

I used it for a week with no problems.

Then I installed a program called OSL 20000 Boot Manager.suggested by a friend to make it possible to install more than two OS. I also installed another program called Driver Magician also suggested by him although I had already installed the proper drivers but thought it might be useful in future.

After installing those two programs I booted the computer 2-3 times & it seemed to work fine.

But next morning when I started the system it will not detect the Hard Disk at all.
If I connect the second Hard Disk, then that hard disk also doesn’t get detected. So this new hard disk makes all other working Hard Disks ( with XP on them ) also disappear.

I tried normal checks like cable & power cord & drive does spin & tried to repaire thru Vista DVD but it says there is no hard drive.

I need professional help because I have lots of data on it ( most I have backed up ) but returning for a replacement would leave all my data on it including personal data.

Can you guys help ?

Thank You.

 

Does the PC BIOS recognize the drive? If not, then the drive is most likely not getting power. If you remove the side of the case and power up and gently touch the hard drive, you should be able to feel a light vibration as it is spinning. If not, then it is definitely not getting power. But if it is getting power and spinning but the BIOS doesn't recognize the drive, try using a different data cable and/or try connecting it to a different motherboard header. If none of this works, remove the drive and try it in another PC (if possible) or pop it into an enclosure and hook it up via a USB port on a healthy PC. If the drive comes up when connected to a different PC, then we know the problem is with your Dell. If the drive doesn't come up anywhere, then it is likely DOA and should be eligible for a warranty replacement. You won't get your data back, but you'll get a new drive.

 

Thanks dlb,

1. It does spin
2. Another two drives work with same power & SATA cable
3. It does not get detected in another SATA port, cable & power supply on the same machine. I do have another PC but no SATA ports so I can't test on it.
4. It does one strange thing that might give you a clue. Here it is :

I have two drive slots & two SATA cables. If I connect another working drive ( with XP on it ) then both drives don't get detected & can not boot even with a good drive.

It is a Seagate SATA 500 GB drive. So I tried to find something on Seagate site that would help identify the problem but couldn't figure out which software tool to use. Can you please look into that ? There was something called "Seatools" a diagnostic utility but I have no knowledge of DOS.

The local guy is willing to give me a new drive but I can not risk giving my personal data away with this defective drive. So either I have to find a solution or destroy the drive. ( I do have 95% data on a back up ).

Can you help please ?