What does "WCHS" in partinfo mean?

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What does "WCHS" in partinfo mean?

Postby sigi » Mon Nov 28, 2016 11:38 am

What does "WCHS" in partinfo mean?

Partinfg (example attached) shows in the headline describing the hard drive CHS and WCHS data. What does WCHS stand for? I could not find this abbreviation neither on terabyteunlimited.com nor with Google.

While at partinfg, could you please explain the data and their meaning in the diffent columns of the table or give a link to a document that contains this exlplanation?
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Re: What does "WCHS" in partinfo mean?

Postby TeraByte Support » Mon Nov 28, 2016 8:55 pm

windows reported chs values.


"sigi" wrote in message news:12905@public.bootitbm...

What does "WCHS" in partinfo mean?

Partinfg (example attached) shows in the headline describing the hard drive
CHS and WCHS data. What does WCHS stand for? I could not find this
abbreviation neither on terabyteunlimited.com nor with Google.

While at partinfg, could you please explain the data and their meaning in
the diffent columns of the table or give a link to a document that contains
this exlplanation?

TeraByte Support
 
Posts: 2310
Joined: Thu May 05, 2011 3:37 pm

Re: What does "WCHS" in partinfo mean?

Postby sigi » Tue Nov 29, 2016 8:42 am

Thank you.
A short explanation of the differences in the Terabyte and Microsoft calculation methods would be helpful.
Intel Core i3 540 | 2 SATA-HDD with 640 GB each | Win7 Pro x64
sigi
 
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Re: What does "WCHS" in partinfo mean?

Postby sigi » Tue Dec 06, 2016 11:27 am

Is the difference in calculation methods so well known or so unimportant that nobody cares to answer or to support my request for an answer?

Perhaps a link to an explanation would do.
Intel Core i3 540 | 2 SATA-HDD with 640 GB each | Win7 Pro x64
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Re: What does "WCHS" in partinfo mean?

Postby TeraByte Support » Tue Dec 06, 2016 11:29 am

it just reports the values for support.


"sigi" wrote in message news:12941@public.bootitbm...

Is the difference in calculation methods so well known or so unimportant
that nobody cares to answer or to support my request for an answer?

Perhaps a link to an explanation would do.

TeraByte Support
 
Posts: 2310
Joined: Thu May 05, 2011 3:37 pm

Re: What does "WCHS" in partinfo mean?

Postby sigi » Tue Dec 06, 2016 7:24 pm

Do you mean support rendered by Terabyte or Microsoft to me if I have a problem with partitions?

Is the difference in calculation methods so unimportant and on the other hand so complex that it is not worth the effort of explaining?
Intel Core i3 540 | 2 SATA-HDD with 640 GB each | Win7 Pro x64
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Re: What does "WCHS" in partinfo mean?

Postby Brian K » Tue Dec 06, 2016 8:11 pm

You can use WCHS cylinders in this calculation...

http://www.deathwombat.com/diskgeometry.html

WCHS cylinders don't rollover after 1024.
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Re: What does "WCHS" in partinfo mean?

Postby sigi » Thu Dec 08, 2016 10:37 am

Thank you for giving me the keyword "diskgeometry" I can search for in Google.
However, this gives me a lot of hits but none of them mentions WCHS including your link.

Your reference to "rollover" does not tell me anything. What does it mean?
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Re: What does "WCHS" in partinfo mean?

Postby Brian K » Thu Dec 08, 2016 12:58 pm

The CHS system is archaic and can't read more than 1024 cylinders. WCHS will read the correct number of cylinders. Here is an example from my SSD. Disk Management shows it as 447.13 GiB. WCHS shows 58369/255/63

1 cylinder = 255*63 = 16065 sectors = 16065*512/1000 = 8225.28 KB = 8.22528 MB

8.22528 MB = 8.22528/1.024^3 = 7.6604 MiB

58369 cylinders = 58369*7.6604/1000 = 447.13 GiB
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Re: What does "WCHS" in partinfo mean?

Postby sigi » Fri Dec 09, 2016 6:39 pm

Thank you Brian for this very helpful explanation.
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