Sign in with
Sign up | Sign in
Your question

will ata66 and ata100 HDD force ata66 speed?

Last response: in Storage
Share
Anonymous
a b G Storage
February 15, 2001 12:39:25 AM

Hi

If I put both a ATA66 and ATA100 on a single ATA100 controler will the ATA100 hard drive transfer rate be limited to ATA66?

Thanks

Gumby7
Anonymous
a b G Storage
February 15, 2001 12:55:51 AM

The drives are going to run at the speed that they were made for. So if you have the ATA 100 drive on the ATA 100 controller then it will run at ATA 100, and if you have a ATA66 drive on the ATA 100 Controller then it will run at ATA 66.



Lars Coleman
http://home.earthlink.net/~larscoleman
Anonymous
a b G Storage
February 15, 2001 6:57:14 PM

hey gumby7
Do you mean.
1 100 controller
ata66 on primary
ata100 on secondary
will it slow the 100 down to 66?
if that's what your asking by having both drives on the same controller but diffrent channels.

I am also wondering the same thing.
Related resources
February 15, 2001 7:02:49 PM

If each is master on its own channel, then the ATA100 will be 100 and the ATA66 will be 66.

If you have them both on the same channel (master/slave)then they will both run at 66.

Not that you'd notice a difference between 66 and 100 anyway...

"There's no such thing as gravity, the Earth just sucks"
Anonymous
a b G Storage
February 15, 2001 8:30:23 PM

>>>If you have them both on the same channel (master/slave)then they will both run at 66. Not that you'd notice a difference between 66 and 100 anyway...<<<

This is hogwash.. and you're not the first person to say it. So it should stop. It may happen in isolated cases. But in general, the bios of an ATA controller has the ability to negotiate and agree upon a transfer rate with each individual drive on the same channel or not. Most of them will auto detect the fastest possible rate capable by the drive and use it. If that's ATA 100 for a slave and ATA66 for a master on secondary channel, it's more than capable of handling that.



***Hey I run Intel... but let's get real***
February 15, 2001 8:45:06 PM

If you would like it to stop, why not post a link to a white paper, etc. that supports your statement? If you do then I will be the first to say that you're right.

I was just repeating what I've always been told.

Apparently this is a touchy subject for you...

"There's no such thing as gravity, the Earth just sucks"
Anonymous
a b G Storage
February 15, 2001 11:55:10 PM

<A HREF="http://www.quantum.com/src/whitepapers/wp_ultraata100.h..." target="_new">http://www.quantum.com/src/whitepapers/wp_ultraata100.h...;/A>

Only white paper you're going to get. Certainly doesn't mention any place where running an ATA 100 drive with ATA 66 will cause both to run in ATA 66 mode. The only confusing paragraph in the paper that could be interpreted as such..still doesn't say this.

>>Older Ultra ATA/33 or ATA/66 drives can be easily connected to the ATA/100 interface without modifying existing software or components. The interface will automatically step down to their operating level when transferring data between the host and these older drives. New ATA/100 drives can be purchased and used both in newer ATA/100 systems (that will take advantage of the next generation devices via the higher-speed interface) and in older ATA systems. In these cases, the new Ultra ATA/100 drives will transfer data to and from the host at the host’s slower speed. An Ultra ATA/100 adapter card solution can be installed in PCs with older ATA chip sets to step up to ATA/100 with newer, Ultra ATA/100 drives.<<

Although that could create confusion and probably does. It still doesn't mean running an ATA 100 drive on the same channel with a slower mode drive will downgrade it.

<A HREF="http://www.promise.com" target="_new">http://www.promise.com&lt;/A>
PCS FAQ #52 Solution:
"There are only two reasons why the Ultra100 BIOS won’t detect an ATA/100 capable HDD as such. Some HDDs (many WD ATA/100 HDDs) require you to run a utility to enable the ATA/100 feature. These utilities can be obtained from the HDD manufacturer. In addition, only a certain type of IDE cable can support data transfers of up to 100MB/s. These 80-wire/40-pin cables (the Ultra100 comes with one) have twice as many grounding wires as traditional IDE cables. This dramatically decreases the debilitating line noise that a 40-wire/40-pin IDE cable would produce when attempting ATA/100 transfers. The biggest problem line noise creates is data corruption. This is why the Ultra100 BIOS will downgrade itself to ATA/33 transfers when it detects the use of a traditional 40-wire/40-pin IDE cable."

Not either of the two reasons is because "you are running a drive on the same channel that is not capable of ATA 100 mode".

>>I was just repeating what I've always been told.<<

And I've seen people say the contrary, especially from those who've used ATA100 cards and know from experience including myself. And on a lot of occassions when I've read people indicate what you have, it's usually to a question of "oh I have ATA 100 and ATA66 on same controller.. system is sluggish during some disk activity between the two", which is because both are on the same controller not because both are running at ATA 66.

>>Apparently this is a touchy subject for you...<<

No it's not touchy because I said it's hogwash or that other people have said it. It is hogwash and other people have said it. It's misinformation, which might be personal, because as you've indicated, it's like a disease.



***Hey I run Intel... but let's get real***
Anonymous
a b G Storage
February 16, 2001 12:19:23 AM

So a new IBM ATA100 and a one year old Maxtor ATA66 on the same ATA100 cable connected to the ATA100 controller on a CUSL2-C will run at ATA100?

Obviously the 66 will still be 66, and transfering between the two will be limited by the 66.

Thanks
Anonymous
a b G Storage
February 16, 2001 1:26:12 AM

>>Obviously the 66 will still be 66, and transfering between the two will be limited by the 66.<<

Well no that is not the limiting factor here since the IBM nor the old Maxtor can neither push ATA 66 and certainly not ATA 100 to it's limits. The problem is the system actually has to pause and stop communicating with one device to communicate with the other, which has nothing to do with the transfer mode. Furthermore even on separate channels, the limiting performance of the Maxtor will be a bottleneck for data transfers from the maxtor to the IBM (depending on how the Maxtors read compares to the IBMs write speed). But in general for similar performing drives when the bus bottleneck is removed, this will always be the case cause the write capabilities will be slower than read capabilities. And this only applies to transfers between drives.. Any application run or data read from one drive it won't matter.

Hypothetically.. if the IBM or the Maxtor were able to push transfers beyond 66MB/s then that transfer mode would be a bottle neck and it would apply if you put them on separate channels, the same channel, different cards. It would always apply no matter what you did. But that's all hypothetical and the drive's can't, they don't, and the transfer mode isn't.

And these issues are beyond the simple question brought up, which is can a drive operate in ATA 100 mode on the same channel as drive operating in lower mode. The answer to that is emphatically yes. Even though this fact makes no real world difference in today's performance, in your hypothetical world where ATA 66 does create a bottleneck, it makes a very big difference as anything run just off the ATA100 drive in ATA100 mode would transfer beyond 66MB/s.

***Hey I run Intel... but let's get real***
Anonymous
a b G Storage
February 16, 2001 3:14:27 AM

You may be correct but then why bother trying to get a buggy A7V/VIA chipset to work at ATA100?

If the best hard drive can't exceed ATA66 why bother?

Gumby7
Anonymous
a b G Storage
February 16, 2001 5:08:09 AM

>>You may be correct but then why bother trying to get a buggy A7V/VIA chipset to work at ATA100?<<

I am correct and I wouldn't.. but that wasn't the question you asked.

The answer to your orginal question is no.. If you are having problems (why didn't you just say so?) with this on that particular board it could be a jumper issue or isolated quirkiness. The 75GXP has 4 master settings.. you should be using device 0 slave present 16 head (G-H, E-F).

And buggy is an opinion or relative either way (although if you're having problems I understand it appears awfully buggy.. been there done that).. many people have no problems running ATA 100 drives either by themselves or in some conjunction with an older drive on that board. In some cases, it would even be more work to get the ATA100 to operate at a lower transfer mode while connected to the ATA100 controller. And the ATA100 controller on the A7V is not VIA, it's Promise. VIA has no input as to how that is integrated with their chipset, they may have supported ASUS in some way but I seriously doubt it.

***Hey I run Intel... but let's get real***
February 16, 2001 12:53:34 PM

"Although that could create confusion and probably does. It still doesn't mean running an ATA 100 drive on the same channel with a slower mode drive will downgrade it."

And nowhere in the white paper does it say that running an ATA100 drive with a slower drive WON'T downgrade it.

I guess the point is that I've never seen documentation from a legitimate source explaining exactly what occurs in this situation. That's why I asked if you knew of any whitepapers.

If there was documentation explaining it one way or the other, then we could eliminate the "disinformation" once and for all.

Of course, this is all pretty much a moot point at this time since no drives can acheive speeds beyond ATA66 anyway.



"There's no such thing as gravity, the Earth just sucks"
Anonymous
a b G Storage
February 16, 2001 4:24:07 PM

question...
if you say that no drives can achive over 66
why do they sell them as ATA/100 speed.
is that just a marketing ploy?
Anonymous
a b G Storage
February 16, 2001 6:54:55 PM

>>if you say that no drives can achive over 66<<

It's not if I say, hard drives of any sort just do not have the mechanical ability for sustained transfers over 66MB/s.

>>is that just a marketing ploy?<<

Isn't everything to some degree? But there might be some RAID configs that utilize that bandwidth over 66MB/s...and drives are improving everyday(although I would expect miracles until they develop head technology that can handle the aureal densities of high-end ATA drives at 10k and 15k speeds). It's good that ATA100 comes along now. Would you rather we develop drives that can deliver beyond 66MB/s and not have a transfer mode fairly entrenched in systems that can handle it? or vice versa as it stands now. But yeah if you give a company something else to tout about their product, they are generally going to.




***Hey I run Intel... but let's get real***
!