UDMA 5 in bios when booting up, does this tell me it's running at ATA-100?

[Detoyminador_]

???

 

[progiciel]

Yes, it does.

 

[bonkers325]

tee hee yes

 

[Schola]

How can that be then. My 2 IBM 75 GXP say they are running in UDMA Mode 5 on a ASUS K7M R1.04, but as far as I know the K7M does not support ATA-100, only ATA-66. So how can this be? Just Curious?

Schola

 

[AMB]

UDMA 5 is ATA-100, I do not know what ATA-66 is, but 33 is UDMA 2

 

[thorin]

Here's a quote from an older post of mine:

ATA Short for AT Attachment, simply means the integration of the HD controller onto the HD itself.

ATA Drive Standards:
?ATA (IDE) - 16 Bit interface supporting PIO modes 0,1 and 2
?ATA-2 (Enhanced IDE or Fast ATA) - Support for PIO modes 3 & 4, DMA modes 1 & 2. Also supports LBA (Large Block Addressing and block transfers).
?Unltra-ATA (Ultra DMA, ATA33, DMA33) - Supports DMA mode 3 running at 33mbps.
?ATA66 (Ultra DMA66, DMA66) - Runs at 66mbps. DMA mode 4.
?ATA100 (Ultra DMA100, DMA100) - Runs at 100mbps. DMA mode 5.

Although they get very confused and misinterpreted (as seen above) ATA is a drive configuration. IDE and EIDE are interface standards. DMA is an access method for the drive(s), which allows transfer to occur between the drive and RAM while bypassing the CPU.

ATA100 is the current step, with speeds of 100mbps. Shortly we'll see Serial ATA with speeds starting at 150mbps and progressing to 300mbps then 600mbps.

World's First Serial ATA Drive
(Gotta love those small cables, size of Phone cable or CAT5)
NOTE: The link right above is currently broken, it isn't my fault they've moved things, I was on their site this morning and it's giving 404s all over the place)

"INTEL DEVELOPER FORUM CONFERENCE, SAN JOSE, Calif. - August 24, 2000 - Seagate Technology, APT Technologies, Inc. and Vitesse Semiconductor Corporation today unveiled the first Serial ATA disc drive, giving a glimpse into the future of ATA disc drive technology. The drive is natively attached to an Intel® Pentium® 4 processor system through an APT Serial ATA PCI Host Bus Adapter, featuring a 1.5 Gbps transfer rate. The prototype demonstration combines technologies from Seagate, APT, Intel Corporation and Vitesse.
It features a Seagate disc drive with its Serial ATA board, using APT's Serial ATA Link and Transport layers logic and Vitesse's 1.5 Gbs CMOS transceiver, attached via Serial ATA to APT's Serial ATA to PCI host bus adapter."


SerialATA Preview

Thorin

 

[dirtboy]

I recently bought a 75GXP and ran it on an Abit BH6, which only has a ATA/33 controller on it. During boot, the BIOS detected it as a UDMA Mode 5 device. Hmmmm... turns out that the drive is set at the factory to run as a UDMA Mode 5 device on a ATA/100 controller. I did notice that the drive was signifcantly slower than my 2 year old IBM drive.

So, I d/led the program and set the drive to run as a UDMA Mode 2 (ATA/33) device and performance skyrocketed. A quick e-mail to IBM and they responded that you need to set the drive to whatever your controller can handle.

If you only have an ATA/66 controller, I recommend setting your drive to properly run on it and just because it reports as a UDMA Mode 5 device doesn't mean it is running at ATA/100, it means it's trying to but it can't.