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MegaZone wrote:
> Basically ALL hard drives are sold using base10.
> 80GB == 80,000,000,000 Bytes.  But nearly all operating
> systems - including TiVo - use base2.  80,000,000,000 Bytes = 74.5GB.

After following a link on Slashdot to the LDB (Long Data Block) standard,
I found something interesting regarding IDEMA standardized disk sizes.

A 50 GB disk is defined has having a logical block count of 97696368,
which is 50,020,540,416 bytes = 48,848,184KiB = 47,703.3MiB = 46.59GiB.
(That number, 97696368, is 2*2*2*2 * 3*3*3*3 * 7 * 11*11 * 89.)

Each additional 10 GB has an incremental LBA count of 19535040,
which is 10,001,940,480 bytes = 9,767,520KiB = 9,538.6MiB = 9.32GiB.
For logical cylinders consisting of 255 head and 63 sectors, that
would be 1,216 cylinders (64*19).

http://www.idema.org/_smartsite/modules/local/data_file/show_file.php?cmd=download&data_file_id=1066

   The LBA count shall be calculated using the following formula:
   LBA count = (97696368) + (1953504 * (Desired Capacity in Gbytes - 50.0))

That means an 80 billion byte disk holds 74.5 gibibytes (using binary "giga").
For "kibi", "mebi", "gibi", "tebi", see http://en.wikipedia.org/wiki/Binary_prefix

"Size"      LBA             bytes     kibibytes   mebibytes gibibytes tebibytes
  50   97696368    50,020,540,416    48,848,184    47,703.3    46.585
  60  117231408    60,022,480,896    58,615,704    57,241.9    55.900
  80  156301488    80,026,361,856    78,150,744    76,319.0    74.530
 100  195371568   100,030,242,816    97,685,784    95,396.2    93.160
 120  234441648   120,034,123,776   117,220,824   114,473.4   111.790
 160  312581808   160,041,885,696   156,290,904   152,627.8   149.051
 180  351651888   180,045,766,656   175,825,944   171,705.0   167.681
 200  390721968   200,049,647,616   195,360,984   190,782.2   186.311
 250  488397168   250,059,350,016   244,198,584   238,475.1   232.886
 300  586072368   300,069,052,416   293,036,184   286,168.1   279.461
 320  625142448   320,072,933,376   312,571,224   305,245.4   298.091
 400  781422768   400,088,457,216   390,711,384   381,554.0   372.611
 500  976773168   500,107,862,016   488,386,584   476,940.0   465.762 0.455
 750 1465149168   750,156,374,016   732,574,584   715,404.8   698.638 0.682
1000 1953525168 1,000,204,886,016   976,762,584   953,869.7   931.513 0.910
1500 2930277168 1,500,301,910,016 1,465,138,584 1,430,799.4 1,397.265 1.365
2000 3907029168 2,000,398,934,016 1,953,514,584 1,907,729.1 1,863.017 1.819
2500 4883781168 2,500,495,958,016 2,441,890,584 2,384,658.8 2,328.768 2.274
3000 5860533168 3,000,592,982,016 2,930,266,584 2,861,588.5 2,794.520 2.729


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