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Author Topic: Why does my computer have less available memory than advertised?  (Read 2290 times)

Offline krool1969

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When I bought my new laptop last year it was advertised as having a 300Gb hard drive. In fact it only has a 273Gb. A few weeks ago I spent $100 on a 1Tb (1000Gb) hard drive. When I hooked it up I found it is only 931Gb.

This seems to be a common practice with computers and computer assessors. Is there a good reason why we only get about 90% of the advertised memory?
« Last Edit: 02/03/2013 12:31:54 by chris »


 

Offline RD

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Re: Why am I shorted on my computer memory?
« Reply #1 on: 01/03/2013 23:35:47 »
It's a decimal / binary confusion thing ...

1 GB = 1 gigabyte = 1000000000 bytes

1 GiB= 1 gibibyte =  1073741824 bytes

so can appear to be short changed by 7%

https://en.wikipedia.org/wiki/GiB
« Last Edit: 01/03/2013 23:38:39 by RD »
 

Offline syhprum

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Re: Why am I shorted on my computer memory?
« Reply #2 on: 01/03/2013 23:44:37 »
When you set up new drives with an OS they make a special separate section for it.
 

Offline CliffordK

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Re: Why am I shorted on my computer memory?
« Reply #3 on: 02/03/2013 00:44:27 »
This has been an issue for quite some time
Drives are sold with unformatted capacity, even if they come preformatted.

You have both low level formatting, including the delineation of tracks and sectors (which you may not  be able to change), as well as high level formatting including the FAT table and basic directory structure.

Memory based devices (USB thumb drives & solid state drives) don't need the same low level formatting as standard disk drives, and the capacities should be more accurate.
 

Offline David Cooper

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RD is correct. If you buy a 16GB flash drive and look at its actual size it'll be closer to 15GiB. This has nothing to do with partitions or formatting.

When Windows tells you how big a drive is, it uses GiB (but calls it GB - GB is ambiguous and can be used for both systems of counting).

When manufacturers sell drives, they always give you it in GB (and not GiB) - this is necessary because most consumers will automatically buy the drives with the bigger numbers attached to them without checking the small print.
 

Offline MrVat7

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They are cheaters , they should advertise the available memmory .
 

Offline McKay

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No, no - the hard drive manufacturers are the ones geting it right. The OS is getting it wrong - showing GiB's as if they GB's. Mac OS, actually, made an update that shows it right now.. I hope microsoft does the same.
 

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