http://www.samsung.com/Products/HardDiskDrive/support/faqs/faqs_20050422_0000115202.htm
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Hard Disk Drive
Date Subject
Apr 22,2005 UDMA-6(UDMA133) not support
Question
My drive is recognized as UDMA 100 while it is
UDMA 133.
Answer
* Syptom
The drive is recognized as UDMA 100 while it
is UDMA 133.
* Cause
Because some motherboards have a problem for
supporting UDMA-6(133), we set UDMA mode as
UDMA-5(100) during the production.
* Solution
Please use the HUTIL for confirming or
switching the UDMA mode on the drive if your motherboard supports UDMA-6.
Because some motherboards have a problem for
supporting UDMA-6(133), we set UDMA mode as UDMA-5(100) during the
production.
You can switch the drive's UDMA modes with the
udma6.exe or HUTIL. (HUTIL has been uploaded on Utilities page) Switching
UDMA modes with the HUTIL does not effect the data on the drive.
However we strongly recommend that you back
your data up prior to executing these tools.
After switching the drive's UDMA modes, you
should also confirm whether your systems's chipset driver is the latest
version or not.
And Win-XP is the only OS that you can see the
UMDA mode as 'UDMA mode-6', other OSs just display something like that 'DMA
mode enabled'.