A couple of quick questions regarding HD's

[Paulr]

Hi,
Can you tell me if ATA-4 is the same as ATA-66?
I purchased an IBM Deskstar 22GXP as an ATA-66 drive.
I have just been to check on the specification of this drive at IBM's web page.
At the top of the profile page on this HD: http://www.storage.ibm.com/hardsoft/...sk/ds22gxp.htm

Under highlights it says:
Interface - Ultra-ATA/66

However, if I scroll further down the page to the specification table for this model it says the following:
Interface ATA-4

Are these one and the same thing?

Question 2:
Under Win98, if I have a drive capable of ATA transfers, I simply goto the properties of the HD under Device Manager and check the DMA boxes.
How do I do this under Win2000?
Of is this something done automatically?

Thanks a lot for any help you can offer.

[Jammrock]

1) Not 100% on this one, but I think that's right. As far as I can tell there are 3 naming conventioned used for hard drives. ATA X, where X is the version of ATA used (i.e. 1, 2, 3, 4). ATA Y, where Y is the transfer speed (i.e. ATA 66). And UDMA Z, where Z is the transfer speed and UDMA is the transfer mode. I may off a bit on the ATA X thing, but I'm pretty sure that's it. The next standard is ATA/UDMA 100 which is coming out this year.

2) You are correct about Win98 and DMA mode.

3) Win2k detects the transfer modes automatically. If you want to double check that they are enabled, go to the Device Manager and go to the properties for the IDE Controller, NOT the hard drive itself. There will be an option that you can select DMA transfers in possible. That one should be selected.

Jammrock

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Athlon 650, Biostar board, 128 MB PC133 (Crucial), G400 32 MB DH, SB Live! w/ Digital I/O, 10/100 NIC, lots of case fans, etc...

[Greebe]

ata mode 4 = UDMA 33

Which MB/controller are you using?

[Paulr]

Hi people,
OK, now I have conflicting information
I have one reply here saying that ATA-4 = ATA-33 and another saying ATA-4 = ATA-66.
I posted on another forum (the good old chaps, obviously not as good as you guys, at ntcompatible) and the replies I got there seemed to think ATA-4 does indeed = ATA-66.
Anyone fancy going for the definitive answer?

I'm running the HD's on a HPT-366 ATA-66 controller, it's the on-board one from the Abit BE6-II Motherboard.
All the standard IDE controllers are disabled (My DVD, CD-RW & ZIP drive all run off an Adaptec 2940).
I just can't see anywehere under Win2000 under properties for the ATA-66 controller to enable DMA transfer etc.

Paul

[Jorden]

As far as I know ATA-4 = UDMA/33. My old BIOS on my Asus P2B always switched to UDMA 2/4 mode, (on some systems even refered to as PIO-mode 4), and this is for UDMA/33 systems only.

The interface on the drive can be UDMA/66, while the drive itself still is UDMA/33. Maybe this is to make it compatible with UDMA/66 controllers? (As I've noticed, though most controllers indicate backward compatibility with UDMA/33 drives, they don't always work that well on these controllers)

Jorden.

[RAB]

Let me add some further confusion to this. I just went to the Maxtor site and was looking at the 7200 rpm drives.

The older Diamond Max Plus 6800 drives are listed as ATA-4/UDMA 66 and their transfer rates are 33.3 MB/s to/from media(disk surface to disk cache chip) and 66.7 MB/s to/from the interface (disk cache chip to the Motherboard chipset).

The newer Diamond Max 40 Plus drivers are listed as ATA-5/UDMA 66. Their transfer rates are 43.2 to/from media and 66.7 to/from interface.

From this, it appears that the ATA number refers to the transfer rate to/from the disk surface and the UDMA refers to the transfer rate from the drive's cache to/from the motherboard chip set.

This would explain the UDMA 33 drives being listed as ATA-4. Both UDMA-66 and UDMA-33 drives transfer to/from the disk surface at 33 MB/s. Its the transfer from drive cache to mobo chipset that's faster on 66's.

RAB

[Paulr]

Right,
So it would appear that the interface from HD (IBM Deskstar 22GXP) to MB (ABit BE6-II) is ATA-66.
However, the transfer from the 2MB Cache to the disk surface is only ATA-33.
Now that is cleared up :-)
Imagine this HD was put beside a HD running at ATA-66 all through, are you going to notice the difference?
I feel 'kind of' cheated as I bought this drive as an ATA-66 unit, but of course it does have an ATA-66 interface at the MB end of things, so I got what I asked for!!
Sheesh

[RAB]

Don't feel cheated. The Maxtor is the first one I've seen calling itself ATA-5 (Five) because its disk to drive cache is 43MB/s instead of the current standard of 33. No drive that I am aware of is 66 between disk and drive cache. While the Maxtor claims a modest improvement in the cache to disk spec, it is slower in other areas like average seek times. They claim <9ms, but they test about 12 or 13. The IBM's generally test faster in average seek times.

What this means is that in long reads from the disk, like starting and loading a program or data, the Maxtor is faster. But if you need data while you are using a program or have to access your swap file, the IBM is likely to be slightly faster. You tell me which is more important. I say its a toss up. The difference is small, and without measuring, I doubt you could tell the difference. So again, the IBM is an excellent drive and competitive with anything now in production. Don't feel cheated.

RAB

[Paulr]

Hummmmm.
Now I thought PIO Mode 4 & UDMA Mode 4 were totally different.
Oh well, I guess it's time to see if IBM fancy replying to my e-mail.

[Paulr]

Cheers for your response.
After doing a bit of research it would appear that most ATA-66 drives are in fact hybrid ATA-66/ATA-33.
I've seen only two actually listed as ATA-5, a Maxtor & a Quantum.
Worries over, I know the IBM units tend to be good, latest issue of PC Pro has a 5400rpm IBM beating a load of 7200rpm drives from other manufacturers!

Thanks again

[bongo]

I don't mean to rain on IBM's parade, but Maxttor builds IBM drives...they are the same. If you want a different HD, I suggest Fujitsu or Western Digital. Don't know much about Quantum.

[CHHAS]

Bongo:

I don't know where you got that bit of info, but it's not correct.

Western Digital buys technology from IBM, IBM and Maxtor has nothing in common whatsoever.



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P3 500, 224 MB ram, G400 16SH,
Maxtor DM 40+ 30GB, IBM Deskstar 16GP 10GB, Maxtor 4320 13 GB
SB Live Value

[Paulr]

No way I will touch another Western Digital HD!!
That's the make that has caused me all the problems in the first place.
I hade by big IBM unit and a smaller WD one.
Whenever the WD unit was plugged on the ATA-66 controller the whole PC hung.
Win2000 refused to load.
It also totally hung on a re-installation of Win2000.
According to WD web pages this drive is an ATA-66 drive.
Downloaded and ran their utility, that confirmed it was an ATA-66 drive and ATA-66 was enabled.
SO an ATA-66 WD drive doesn't work on a standard ATA-66 controller, sheesh.
As for IBM drives being made by Maxtor.
That's the fist I've heard about that!
Nobody seems to have mention that anywhere before, I thought IBM made their own drives and actually licensed their technology out??

[Pace]

With regards to the Win2K DMA enabling it's under Device Manager again but 'IDE ATA/ATAPI controllers>Primary IDE Channel>Advanced Settings' Choose Secondary as well It even tells you what mode the drive is currently using.

Paul.

[RAB]

Anand did a review of hard drives recently and if I remember correctly, he pointed out that the WD and IBM drives were identical except for the label. So they are coming out of the same factory. Whether the factory belongs to WD or IBM, I don't know. But they are now the same drives. This might not have been the case last year. I have an old WD and its the noisiest HD I've ever had. Supposedly, the new ones are silent, so I would guess that IBM is now supplying WD.

RAB