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How do I change the number of cylinders my HDD thinks it has?

I have a 500 GB WD Scorpio Blue that now thinks it is a 58GB drive, even in BIOS. I can reformat and repartition this 58GB until I'm "Blue" in the face (sorry) but it doesn't change a thing.

fdisk says the drive has 7,113 cylinders for a total of around 114M sectors, but the drive should have about 976M sectors. I think the correct cylinder value should be 60,801. I can change this in fdisk, but it doesn't actually save this to the drive.

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What BIOS and version are you using? What OS? – Kenneth Murphy Nov 5 '09 at 5:55
It shows up the same in at least 4 different machines. It's definitely the drive itself that has the issue. – PileOfMush Nov 5 '09 at 7:52
up vote 1 down vote accepted

I add this reference, which might apply to your problem:
Restore factory Hard Drive Capacity When HDD Shows up as 32MB

Here's what typically happens; a large capacity hard drive of between 500GB, 750GB, 1TB and 1.5TB suddenly appears to lose most of its capacity for no apparent reason. In many situations the capacity of the hard drive shrinks to 0.0GB or 32MB (and occasionally 32GB) and becomes inaccessible to the Windows Vista.

What's happening, to put it simply, is that the portion of the hard drive responsible for telling the computer how big it is, is mis-reporting that value. We don't have a good technical explanation for what causes this issue to randomly strike PC users, but suffice to say a portion of the drive firmware known as the LBA48, HPA and DCO records becomes corrupted.

This solution uses the Atola Technology HDD Restore Capacity Tool to fix the firmware - use with caution!

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I'll try this first thing in the morning and report success or failure. Thanks. – PileOfMush Nov 5 '09 at 7:58
Thank you. It worked perfectly and it was the simplest tool I've ever seen. Too simple, really, because I wanted to know exactly what was wrong! – PileOfMush Nov 5 '09 at 16:02

There is an overflow bug in some Award and AMI BIOSes that will cause the problem you describe. Flashing the BIOS with a newer version (if available) may be necessary. This will not be the case if you have successfully used a hard drive over 65 GB in this system before.

Also, some older versions of fdisk will not report the size of the drive correctly, due to their use of some 16-bit values internally. I doubt this is the case because the problem presents in the BIOS, but there is more information about the fdisk issue here.

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