If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.
![]() |
|
|
#1 |
|
Junior Member
Join Date: May 2007
Posts: 68
|
Question:
Why is it that SSD drive capacities are in multiples of 4? (ie. Like Samsung's 32 and 64 GB models and Intel's 80GB and 160 GB plus upcoming 320 GB unit). Whereas HDD uses multiples of 10 (ie. 80 GB, 120 GB, 500 GB, 750 GB, 1000 GB/1 TB, 1500 GB/1.5 TB, 2000 GB/2 TB, etc.) Is there an explanation to this? |
|
|
|
|
|
#2 |
|
Darlek ******
Join Date: Jun 2004
Posts: 5,987
|
ssd are probably using binary mesurements whereas hdd's are using decimal
__________________
Guardian of the "Sacred Terabyte of Gaming Goodness™" |
|
|
|
|
|
#3 |
|
Red-headed step child
Join Date: Jun 2004
Location: Guess ;)
Posts: 2,382
|
It's easier than that... Harddrive storage is physical bits on a magnetic platter, you can write almost as many as you care to given the obvious physical constraints. SSD's are memory -- memory is accessed in lines and rows, which are all base-8 addressing. Thus, SSD storage devices are based on components that are sized in powers of two (1,2,4,8,16,32,64,128,256,et al) In your example, a 320GB SSD would be a combination of 128 and 256...
__________________
"...twisting my words" |
|
|
|
|
|
#4 | |
|
ಠ_ಠ
|
Quote:
__________________
"He's more gamerscore than man now." -Referring to Wavey <Burga>stop whining <DeanoC>no |
|
|
|
|
|
|
#5 |
|
Red-headed step child
Join Date: Jun 2004
Location: Guess ;)
Posts: 2,382
|
__________________
"...twisting my words" |
|
|
|
|
|
#6 |
|
Senior Member
Join Date: Sep 2003
Location: Well within 3d
Posts: 2,700
|
Flash components are in powers of two, but at least Intel's flash setups populate 10 channels with those components.
A power of two amount multiplied by 10 means power of four. edit: I meant multiple of four.
__________________
Dreaming of a .065 micron etch-a-sketch. Last edited by 3dilettante; 23-Jan-2009 at 16:32. |
|
|
|
|
|
#7 |
|
Senior Member
Join Date: Feb 2002
Location: gjethus, Norway
Posts: 1,235
|
Hmmmm.
My home PC has a 64 GB SSD in it (an Mtron 7000). Its actual capacity is 64000884736 bytes, which is not actually very close to being a power of 2. |
|
|
|
|
|
#8 |
|
Eric the Half-a-bee
Join Date: Oct 2003
Location: The cat detector van from the Ministry of Housinge
Posts: 1,629
|
Formatted capacity vs. unformatted capacity?
|
|
|
|
|
|
#9 |
|
Senior Member
Join Date: Feb 2002
Location: gjethus, Norway
Posts: 1,235
|
|
|
|
|
|
|
#10 | |
|
Regular
|
SSDs apparently have reserved space in them, as shipped.
http://www.dailytech.com/article.aspx?newsid=14004 Quote:
Jawed |
|
|
|
|
|
|
#11 |
|
Red-headed step child
Join Date: Jun 2004
Location: Guess ;)
Posts: 2,382
|
I'd have to assume that there is a certain amount of "reserve" capacity for error bits. 64GB in memory terms is far more than 64 billion bytes, it's closer to something like 68.7 billion bytes if I did my math correctly.
Two things they accomplish this way... First, and the most obvious, is redundancy in case of bad cells. Second, which may be just be bullhonkey, is to make sure that you're not "getting more than you paid for" -- physical drives have been selling Gigabytes as 1 billion bytes (Rather than 1,073,741,824 bytes) for eons. Why change it now? Edit - Treed like a mofo.
__________________
"...twisting my words" Last edited by Albuquerque; 23-Jan-2009 at 17:48. Reason: I suck at posting quickly |
|
|
|
![]() |
| Bookmarks |
| Thread Tools | |
| Display Modes | |
|
|