oh where oh where could my 20 gigs be

[Dennis Bacon]

HI, I just bought a seagate barracuda 160 gig hard drive... and it's only got 140 gigs.... where did my other 20 go :confused: ... i thought i saw something running away when i opened the package but i didnt think it was 20 gigs so i just let it go...

[rsfnatik]

20GB is pretty small these days... it could be hard to spot :P

[Midknyte]

did you update your bios? are you running windows xp with SP1?

How to Enable 48-bit Logical Block Addressing Support for ATAPI Disk Drives in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;303013

From Western Digital:
137GB (128GB binary) Barrier:
On many systems, the IDE/ATA interface uses a 28-bit addressing which cannot
recognize more than 137GB of storage. To overcome this capacity barrier, drives
higher than this capacity have adopted a 48-bit addressing system which can be supported in newer computer systems with updated controller chips, BIOS codes, and operating system
drivers (refer to your system documentation for more details). If your system does not support drives of this size, you have a few options.

Solution 1:
Western Digital has included a controller card and drivers in many of our retail packaged drives that are greater than 137GB to address this operating system and BIOS limitation. During installation, drives larger than 137GB must be attached to the controller card and the drivers for your operating system must be loaded properly to avoid the risk of data loss. If you need a controller card, please visit our Online Store.

Solution 2:
If the BIOS of your motherboard or controller card supports the drive but Windows does not, see Answer ID 928.

[Peter M]

Disappeared in the marketing department.

"160 GB" drives actually have 160 billion bytes. That's not 160 real gigabytes, that's just 149. This is because a gigabyte is 2^30 bytes not 10^9.

1 kilobyte = 2^10 = 1024 bytes
1 megabyte = 2^20 = 1048576 bytes
1 gigabyte = 2^30 = 1073741824 bytes

So if you're missing around ten real gigabytes, that's just your moving from marketing to technology facts.

If you're missing more, than it might indeed be from the lack of 48-bit LBA addressing capabilities. These must be present in both BIOS and operating system. Without it, the limit is 128 gigabytes, or 137 billion bytes if you like that better.

[Quazar]

BTW there is a class action lawsuit going on about this right now. Maxtor and Seagate are named in it. They have a habbit of misleading the public on this issue.

Ever wonder why IBM and WD and hatachi harddrives are more then Maxtor and Seagate when rated w/ the same gig. That is because Maxtor and Seagate lie a lot more and do a lot of rounding up.

IE Seagate's 120GB SATA drive should be 138350580552821637120 bytes
however it is only
125645926004009467904 bytes or
111 GB

So you lose out on 9 GB per drive.

IBM and WD are a lot better about this issue.

[Peter M]

Yet still, it's been done like that forever.

First up were Quantum waaaaay back in time, with their first "LP" series drives. Advertized as 105 MB, they actually had 100.3, and the fine print said "Quantum defines 1 MByte to be 1,000,000 bytes". As if companies were to define math.

Seagate did worse back in those days, their model numbers reflecting the unformatted capacity of their drives - including sector gaps, bad sector spares and everything. E.g. the "ST225" drive looked like a 25 MByte, but had no more than 20.3 usable.

As long as the consumer sheep flock toward the largest number on the shelf, it'll stay like that.

[Baddog]

In other words, it is like an AMD: xp2400 = 1995 MHZ:D

[Dennis Bacon]

ugh... *puts up middle finger* F U SEAGATE LYING LLAMAS

[Peter M]

Well at least Seagate stopped that "unformatted capacity" nonsense many years ago. Now their model numbers encode actual capacity - in marketing "gigabytes", though.

AMD at least doesn't say "Our MHz are different from yours", they put a performance rating number on it.