MultiDrive – free backup, clone & wipe disk utility from Atola Technology

Main » Forums home » Research and development

All times are UTC - 5 hours [ DST ]

Forum rules


Please do not post questions about data recovery cases here (use this forum instead). This forum is for topics on finding new ways to recover data. Accessing firmware, writing programs, reading bits off the platter, recovering data from dust...



Post new topic Reply to topic  Page 1 of 1
  [ 7 posts ] 
  Previous topic | Next topic 
Author Message
Asque
 Post subject: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: December 6th, 2010, 1:39 
Offline

Joined: March 27th, 2008, 20:37
Posts: 19
After examining the Western Digital VelociRaptor drives

Except for "Capacity" and "User Sectors Per Drive", both the Western Digital VelociRaptor 450 GB (WD4500HLHX) and Western Digital VelociRaptor 600 GB (WD6000HLHX) hard disk manufacturer specifications are identical, including the weight specification.


At this time, I do not have a Western Digital WD4500HLHX drive to examine.

Are the WD4500HLHX model drives WD6000HLHX drives using different firmware?
Top
 Profile  
 
dmarques
 Post subject: Re: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: December 7th, 2010, 4:15 
Offline

Joined: November 6th, 2006, 6:58
Posts: 1752
Most probably they have different firmware, and the 600gb version uses one more head than the 450gb.
Top
 Profile  
 
fzabkar
 Post subject: Re: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: December 7th, 2010, 19:42 
Offline
User avatar

Joined: September 8th, 2009, 18:21
Posts: 16972
Location: Australia
WD's spec sheet states that the two drives have identical maximum sustained data transfer rates, 145MB/s. This would confirm that they are using identical platters, and that the difference is in the number of heads.

http://www.wdc.com/wdproducts/library/S ... 701284.pdf

_________________
A backup a day keeps DR away.
Top
 Profile  
 
Doomer
 Post subject: Re: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: January 30th, 2011, 0:27 
Offline
User avatar

Joined: September 29th, 2005, 12:02
Posts: 3577
Location: Chicago
450GB has 5 heads
600GB has 6 heads

_________________
SAN, NAS, RAID, Server, and HDD Data Recovery.
Top
 Profile  
 
fzabkar
 Post subject: Re: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: January 30th, 2011, 1:00 
Offline
User avatar

Joined: September 8th, 2009, 18:21
Posts: 16972
Location: Australia
Doomer wrote:
450GB has 5 heads
600GB has 6 heads

That works out to 90GB per head for the 450GB drive, and 100GB per head for the 600GB.

Are you sure that's correct?

Instead, 4 heads versus 3 heads would give identical figures of 150GB per head for each drive.

_________________
A backup a day keeps DR away.
Top
 Profile  
 
Doomer
 Post subject: Re: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: January 30th, 2011, 1:59 
Offline
User avatar

Joined: September 29th, 2005, 12:02
Posts: 3577
Location: Chicago
fzabkar wrote:
Are you sure that's correct?

positive

_________________
SAN, NAS, RAID, Server, and HDD Data Recovery.
Top
 Profile  
 
fzabkar
 Post subject: Re: WD VelociRaptor 450 GB vs. WD VelociRaptor 600 GB
PostPosted: January 30th, 2011, 6:38 
Offline
User avatar

Joined: September 8th, 2009, 18:21
Posts: 16972
Location: Australia
AFAICS, that would mean that the 450GB drive is short stroked, which would suggest that it should have better average seek times.

I notice that the 300GB, 150GB, and 74GB models have identical maximum sustained data transfer rates of 126 MB/s. This would suggest that they have identical data densities of 75GB per head. So the number of heads would be 4, 2, and 1, respectively.

The 600GB and 450GB have a transfer rate of 145 MB/s. This would imply that their data density is ...

(145 / 126)^2 x 75 = 99.3 MB per head

This confirms that they have 6 and 5 heads, respectively.

_________________
A backup a day keeps DR away.
Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  Page 1 of 1
  [ 7 posts ] 

Main » Forums home » Research and development

All times are UTC - 5 hours [ DST ]

Who is online

Users browsing this forum: No registered users and 5 guests

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Switch to mobile style
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group