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). www.idema.org/wp-content/plugins/download-monitor/download.php?id=1223 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 "GB" 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 1 tebibyte 1,099,511,627,776 1,073,741,824 1,048,576 1,024 1.000 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 2 tebibyte 2,199,023,255,552 2,147,483,648 2,097,151 2,048 2.000 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 4000 7814037168 4,000,787,030,016 3,907 018,584 3,815,447.9 3,726.023 3.639 4 tebibyte 4,398,046,511,104 4,294,967,296 4,194,304 4,096 4.000 5000 9767541168 5,000,981,078,016 4,883,770,584 4,769,307.2 4,657.527 4.548 6000 11721045168 6,001,175,126,016 5,860,522,584 5,723,166.6 5,589.030 5.458 7000 13674549168 7,001,369,174,016 6,837,274,584 6,677,025.9 6,520.533 6.368 8000 15628053168 8,001,563,222,016 7,814,026,584 7,630,885.3 7,452.036 7.277