# Accessing a 160 gig drive with the A7V133?

Discussion in 'Asus' started by at50, Mar 18, 2005.

1. ### at50Guest

Hi,

I am setting up an old PC as a file store instead of throwing it away
and have bought a samsung 160 gig drive. This board has the promise
ata100 controller (pdc20265r) which I have since discovered being
ata100 only supports upto 128 gig drives. DOH!

Unfortunately I didn't check this first but I have upgraded the BIOS
to AVU1009 and the promise controller to 2.00.0.29 and now I can see
149 gig of the drive, sooo close.

Many thanks for reading and any help GREATLY appreciated.

Cheers,
Tom

at50, Mar 18, 2005

2. ### MuttleyGuest

I know it sounds stupid, but 149GB is the correct size reported by a PC for
a 160GB Hard Drive.

This is due to the difference between the Decimal Gigabyte used by Harddrive
manufacturers, and the Binary Gigabyte used on a PC.

The following text was copied from Samsung's FAQ pages for this issue.
----------------------------
Capacity of an 80-GB Hard Drive Reported as 74 GB
This is because of the dual meaning of the word "gigabyte," depending on
whether it's calculated in binary (base-2) or decimal (base-10) mathematics.
A gigabyte means 109 (1,000,000,000) bytes. A gigabyte also means 230
(1,073,741,824) bytes.

An 80-gigabyte hard drive has a capacity of 80 billion bytes. Since we
think in terms of base-10, when we say "gigabyte" we mean the decimal
gigabyte. A computer's architecture is designed on powers of two, so when a
computer says "gigabyte," it means the binary gigabyte.

Therefore, an operating system may display the capacity of an 80-gigabyte
hard drive as 74.5 gigabytes. There will appear to be 7.4 percent fewer
gigabytes, but each is also 7.4 percent larger.

In much the same way that a tree is the same size whether its height is said
to be 25 feet or 8.2 meters, 80 decimal gigabytes and 74.5 binary gigabytes
both refer to exactly the same capacity, 80,000,000,000 bytes.

The same dual meaning also exists with other units:

Binary Value Unit Decimal Value
1,024 210 kilobyte (kB) 103 1,000
1,048,576 220 megabyte (MB) 106 1,000,000
1,073,741,824 230 gigabyte (GB) 109 1,000,000,000
1,099,511,627,776 240 terabyte (TB) 1012 1,000,000,000,000

To eliminate confusion, in 1998 the International Electrotechnical
Commission devised the terms kibibyte (kiB), mebibyte (MiB), gibibyte (GiB)
and tebibyte (TiB) to refer to the binary units, though these have yet to
attain widespread usage and are not considered part of standard SI
(International System of Units).

Muttley, Mar 18, 2005

3. ### Thomas WendellGuest

It's reporting the correct amount. on my A7V133-C I this week changed my
120GB Samsung for a 200GB Seagate and it shows as 186GB under Windows

10GB --- 9.31 GB
20GB --- 18.63 GB
30GB --- 27.94 GB
40GB --- 37.25 GB
60GB --- 55.88 GB
80GB --- 74.51 GB
100GB --- 93.13 GB
120GB --- 111.76 GB
160GB --- 149.01 GB
180GB --- 167.64 GB
200GB --- 186.26 GB
250GB --- 232.83 GB

--
Tumppi
=================================================
Most learned on nntp://news.mircosoft.com
Helsinki, Finland (remove _NOSPAM)
(translations from FI/SE not always accurate)
=================================================

Thomas Wendell, Mar 18, 2005
4. ### PaulGuest

As Muttley said:

160 / (1.024*1.024*1.024) = 149.01

160 is decimal manufacturer number, 149 is in binary GB.

You are good to go.

Generally ATA133 is an excellent indicator of being able to
handle 48 bit LBA, but select ATA100 controllers can also do
it - you just have to verify for each ATA100 product, whether
there is support or not. It is hard to look up that info
for Promise motherboard chips.

Go here:

Examine the "more" button next to UltraWinDrvB29.zip

http://www.asus.com/support/downloa...&l3_id=4&m_id=1&key_f_name=UltraWinDrvB29.zip

"Support 48bit LBA HDD"

Maybe that is why it is working ?

HTH,
Paul

Paul, Mar 18, 2005
5. ### Axl MykGuest

Some manufacturers count a megabyte as 1000 kb, while others count it as
1024 kb.. With simple addition errors like the former, you get a higher
advertized capacity on a drive, although it's wrong.. It's all an

Axl Myk, Mar 18, 2005
6. ### Roger HamlettGuest

Not actually.
The Mega, and Giga prefixes are clearly defined as 10^6, and 10^9. It was
lazy computer programmers who tried to adopt the alternative. There is a
defined 'proper' form of the MBiByte, and GBiByte for the binary versions.
Microsoft are appalling here, using in some cases a binary KB, and then
multiplying it by 1000, and in other cases 1024, giving two different
sizes for the same file, according to the tool you use...

Best Wishes

Roger Hamlett, Mar 18, 2005
7. ### DaveWGuest

The reported "149 GB" is the FORMATTED capacity of the 160 GB Unformatted
drive. All is well.

DaveW, Mar 19, 2005
8. ### DDGuest

Why in the world are you setting up a server with the drive containing only
one partition?

149 is about all you will get, although to go by my Maxtor 60GB, which gives
me an actual 57.2GB, you might be able to eke out a full 152.5GB, depending
on the actual 'true' physical capacity of the hard drive. Obviously in the
decimal-GB to binary-GB translation mentioned by other respondents, the math
does not work out to that, and my "60GB" drive actually works out to 61.42GB
or so in the decimal math of hard drive manufacturers; however, nobody is
going to advertise a "61.42GB" hard drive.

If you really want to know if you can get more than 149GB, although it's
doubtful, do this:

- make an 80GB partition
- make another partition with the remainder of the drive

If the total is more than 149GB, you are better off with two partitions
anyway.

with 2 partitions than with 2 folders ;p

DD, Mar 19, 2005
9. ### at50Guest

Thank you everyone for your help, much appreciated.

Pretty bloody stupid way of doing things. Was probably ok when hard
drives were alot smaller and the difference was marginal but with say
a 200 or 300 gig drive thats 22 gig difference?

You are spot on Paul, the promise update was for "Support 48bit LBA
HDD" but I was unsure what that meant. Its all good now! Thank you.

If anyone is looking for a quiet hard drive this one is great -
Samsung 160gig SP1614N (not SATA but apparently sata isn't all that
much faster yet in most drives). Bought it based on the spcr review
and it is almost completely silent, set the automatic acoustic
management to quiet and its barely audible when writing.

SPCR Review: http://www.silentpcreview.com/article152-page1.html

Many thanks again guys for all the help.

Cheers,
Tom

at50, Mar 19, 2005