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question, what is udma 33? 2
- Thread starter mussussu
- Start date
UDMA 33 is the original Ultra DMA controller specification (sometimes called Ultra ATA- the two are interchangeable). It allows a higher rate of data transfer than standard IDE, and requires the use of a UDMA-rated ribbon cable. UDMA 33 is rather old, I believe they are up to UDMA 133 at this point. A UDMA hard drive should come with the proper cable (double the data lines of a standard IDE cable). For UDMA to work both the controller and the drive must be UDMA and you must have the proper cable.
UDMA 33 or ATA 33 (both the same! was the interface standard about 4-5 years ago!
It means data transfer up to 33 megabytes a second.
When ATA 66/ UDMA 66 was introduced about 4 years ago the standard course IDE cable (the type still used for CDroms etc) an identical but finer wired cable was introduced to carry the higher data flow.
This finer cable must be used on drives UDMA 66, 100, 133 to achieve the higher data transfer rates these drives can attain, they will still work with the older course cable but data rate transfer will be restricted!
Note* ATA 133 is very new and not readily available at this time but will eventually take over from the current ATA/UDMA 100 standard.
These Ultra IDE/UDMA 66 cables are always supplied with new motherboards specifically for these newer drives.
These faster cables are backward compatible so can be used with the older UDMA 33 Hard drives.
You still use the courser older type for CDroms/Writers/DVD's. Martin Vote if you found this post helpful please!!
It means data transfer up to 33 megabytes a second.
When ATA 66/ UDMA 66 was introduced about 4 years ago the standard course IDE cable (the type still used for CDroms etc) an identical but finer wired cable was introduced to carry the higher data flow.
This finer cable must be used on drives UDMA 66, 100, 133 to achieve the higher data transfer rates these drives can attain, they will still work with the older course cable but data rate transfer will be restricted!
Note* ATA 133 is very new and not readily available at this time but will eventually take over from the current ATA/UDMA 100 standard.
These Ultra IDE/UDMA 66 cables are always supplied with new motherboards specifically for these newer drives.
These faster cables are backward compatible so can be used with the older UDMA 33 Hard drives.
You still use the courser older type for CDroms/Writers/DVD's. Martin Vote if you found this post helpful please!!
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1
- #4
paparazi,
Do you have a link to a website that has more info on what you're talking about? I always thought that the all IDE cables with the same amount of PINS were the same. I've never heard that you had to use a different cable to achieve higher thoroughput. I don't see a difference with the cable that came with my ATA 100 hard drive and the standard IDE cable that came with my mobo.
Do you have a link to a website that has more info on what you're talking about? I always thought that the all IDE cables with the same amount of PINS were the same. I've never heard that you had to use a different cable to achieve higher thoroughput. I don't see a difference with the cable that came with my ATA 100 hard drive and the standard IDE cable that came with my mobo.
Sorry! don't have a link.
It could well be if you are comparing one that came with a UDMA 100 HD and another that came with a newish Motherboard, that they are both the newer, finer, ultra 66 cables that I am talking about, so WOULD look the same.
Do you have an older system you can open up and look at a CDrom cable? you will see the differance straight away.
Connections and pin numbers are just the same although sometimes one pin on the connector is blanked off so sometimes these newer cables carn't be fitted to older boards which have this pin in place, SOMETIMES.
Sorry I can't be more specific. Martin Vote if you found this post helpful please!!
It could well be if you are comparing one that came with a UDMA 100 HD and another that came with a newish Motherboard, that they are both the newer, finer, ultra 66 cables that I am talking about, so WOULD look the same.
Do you have an older system you can open up and look at a CDrom cable? you will see the differance straight away.
Connections and pin numbers are just the same although sometimes one pin on the connector is blanked off so sometimes these newer cables carn't be fitted to older boards which have this pin in place, SOMETIMES.
Sorry I can't be more specific. Martin Vote if you found this post helpful please!!
That helped, actually. However, I have three different pc's. One is an old P166 from 1996. My newest is a P-III 800 MHz using the Intel 815EEB chipset which is ATA 100 compatible. The IDE cables in all 3 systems are using the IDE cables that came with the mobo. All 3 systems have "identical-looking" cables with one pin missing. Since these systems and cables are from 3 different generations, this leads me to believe that the ATA 100 spec doesn't need a special cable.
Am I mistaken? I know there is a new ATA standard on the way, and newer mobos will soon require different IDE cables capable of higher thoroughput.
Am I mistaken? I know there is a new ATA standard on the way, and newer mobos will soon require different IDE cables capable of higher thoroughput.
I don't mean to be rude but this is not rocket science!!!
Ultra IDE 66 cables have been around now for at least 2 years!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
They ARE differant!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
It doesn't take Columbo to see the differance!!!!!!!!!!!!!!
You DO need this finer cable for UDMA 66 upwards to achieve full data transfer rate!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I am NO expert but I am sure about something as simple as this!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Go to your PC parts supplier and have them point out the physical differance!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Martin Vote if you found this post helpful please!!
Ultra IDE 66 cables have been around now for at least 2 years!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
They ARE differant!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
It doesn't take Columbo to see the differance!!!!!!!!!!!!!!
You DO need this finer cable for UDMA 66 upwards to achieve full data transfer rate!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I am NO expert but I am sure about something as simple as this!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Go to your PC parts supplier and have them point out the physical differance!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Martin Vote if you found this post helpful please!!
CyberVenom
Programmer
*sigh*
Regular 40 lead IDE cables can be used on any IDE compatable drive, however if you use them on ATA 66 or higher drive/mobo combos, the combo will revert to the slower ATA 33 speed.
If you use the newer 80 lead ATA cables (or the shielded round ATA cables) there will be less signal degradation, allowing drive and controller to successfully stablish higher speed communications (66, 100, or 133).
If you have been using only the old IDE cables in all of your computers, of course they all look the same. If you were to replace the old IDE cables with some of the higher quality newer cables in the machines where both the drive and the controller support speeds faster than ATA 33, then the hardware would start communicating faster. If you upgrade the cables in machines that don't support ATA 66 or better, it won't do any harm (but no good either).
If you watch the device configuration screen during POST (the second page with the line-art box around the specs), it will say something like: HDD 0: IBM DESKSTAR 40.0Gb/ATA/100
Notice the "ATA/100". That means my drive is communicating at 100Mhz. If I still had the lower grade old IDE cable in my machine it would say: HDD 0: IBM DESKSTAR 40.0Gb/ATA/33
to tell me that it is only able to manage 33Mhz over the low grade cable.
I hope this helps.
If you want to see the physical difference, you can look at the cables at Best Buy or Radio Shack or Fry's. They should be on the reack right next to each other. (ATA and IDE)
Regular 40 lead IDE cables can be used on any IDE compatable drive, however if you use them on ATA 66 or higher drive/mobo combos, the combo will revert to the slower ATA 33 speed.
If you use the newer 80 lead ATA cables (or the shielded round ATA cables) there will be less signal degradation, allowing drive and controller to successfully stablish higher speed communications (66, 100, or 133).
If you have been using only the old IDE cables in all of your computers, of course they all look the same. If you were to replace the old IDE cables with some of the higher quality newer cables in the machines where both the drive and the controller support speeds faster than ATA 33, then the hardware would start communicating faster. If you upgrade the cables in machines that don't support ATA 66 or better, it won't do any harm (but no good either).
If you watch the device configuration screen during POST (the second page with the line-art box around the specs), it will say something like: HDD 0: IBM DESKSTAR 40.0Gb/ATA/100
Notice the "ATA/100". That means my drive is communicating at 100Mhz. If I still had the lower grade old IDE cable in my machine it would say: HDD 0: IBM DESKSTAR 40.0Gb/ATA/33
to tell me that it is only able to manage 33Mhz over the low grade cable.
I hope this helps.
If you want to see the physical difference, you can look at the cables at Best Buy or Radio Shack or Fry's. They should be on the reack right next to each other. (ATA and IDE)
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- #9
The faster drives require twice the number of wires, but one wire is for sheilding. The extra wire is to maintain data integrity at higher transfer rates.
The faster you have data traveling through a wire, the more it tends to create its own magnetic field. Since all the wires are right next to each other they could interfere with each other. Therefore, each data wire has a shielding wire. I have both and they dont look much different. Usually the cables have some indication what they are rated at that is painted or inked on the ribbon. This is usually very hard to see. Some newer cables are bundled in a cable instead of a ribbon, to improve air flow. Usually you would have to buy these separately. If you do not like my post feel free to point out your opinion or my errors.
The faster you have data traveling through a wire, the more it tends to create its own magnetic field. Since all the wires are right next to each other they could interfere with each other. Therefore, each data wire has a shielding wire. I have both and they dont look much different. Usually the cables have some indication what they are rated at that is painted or inked on the ribbon. This is usually very hard to see. Some newer cables are bundled in a cable instead of a ribbon, to improve air flow. Usually you would have to buy these separately. If you do not like my post feel free to point out your opinion or my errors.
paparazi,
I'm not your average-joe computer user. I was merely pointing out that the IDE cables in all 3 systems still use the same number of PINS, regardless if there really is an internal difference with the cables. The IDE cables that came with an ATA 100 mobo are "identical-looking" to my IBM Aptiva system from 1996 in which the IDE cables have never been replaced. I do appreciate your kind reply, however...
ceh4702,
Thanks for your help. Your post has made the most sense so far. I'm going to dig a little deeper to find out more about the differences with standard IDE cables and ones that are meant to interface with ATA 100 (since they appear to exist).
I'm not your average-joe computer user. I was merely pointing out that the IDE cables in all 3 systems still use the same number of PINS, regardless if there really is an internal difference with the cables. The IDE cables that came with an ATA 100 mobo are "identical-looking" to my IBM Aptiva system from 1996 in which the IDE cables have never been replaced. I do appreciate your kind reply, however...
ceh4702,
Thanks for your help. Your post has made the most sense so far. I'm going to dig a little deeper to find out more about the differences with standard IDE cables and ones that are meant to interface with ATA 100 (since they appear to exist).
Sorry CyberVenom, but the "100" in ATA 100 stands for 100 MB/sec not MHz. Also, if you use the wrong cable, nothing in Windows will let you know that the cable is only ATA 33 capable. It just simply won't perform as well - I'm currently researching the differences.
Secondly, the fastest IDE drives actually only get to about 40-45 MB/sec, even though they are ATA 100 compatible. If you've done your homework, you'll know that these drives can peak close to 70 MB/sec, although peak speeds are only attained during sequential reads of large files. So, the extra headroom is nice to have even though current drives will never really reach 100 MB/sec.
Like I said, I'm not your average-joe so please only post a reply if you have a website or source to back it up...
Secondly, the fastest IDE drives actually only get to about 40-45 MB/sec, even though they are ATA 100 compatible. If you've done your homework, you'll know that these drives can peak close to 70 MB/sec, although peak speeds are only attained during sequential reads of large files. So, the extra headroom is nice to have even though current drives will never really reach 100 MB/sec.
Like I said, I'm not your average-joe so please only post a reply if you have a website or source to back it up...
- Thread starter
- #12
CyberVenom
Programmer
Yes, a new mobo should come with cabling.
Sorry cdogg, I have been dealing with processors for the last few days, so the term "Mhz" is kind of stuck in my brain. You are right, of course, it is MB/s.
cdogg, you wanted a link; here it is:
The white paper from Quantum on the ATA-100 specification
Be forwarned, this is a technical document, so if you aren't farmiliar with the technology already, it won't make a whole lot of sense, but there are still some interesting charts & graphs to look at... (that was not directed at you, cdogg - it was for anyone who wanders upon this post unknowingly)
Sorry cdogg, I have been dealing with processors for the last few days, so the term "Mhz" is kind of stuck in my brain. You are right, of course, it is MB/s.
cdogg, you wanted a link; here it is:
The white paper from Quantum on the ATA-100 specification
Be forwarned, this is a technical document, so if you aren't farmiliar with the technology already, it won't make a whole lot of sense, but there are still some interesting charts & graphs to look at... (that was not directed at you, cdogg - it was for anyone who wanders upon this post unknowingly)
CyberVenom,
Nice link! After reading the entire article, my theory about the cables seems to be more correct. If you read the second to last paragraph, you'll notice it says:
"without the need for termination devices, new cabling, or other hardware changes,..."
In your first post, your talking about 40- and 80-conductor cables which are exactly identical except that the 80-conductor provides more shielding. Either one is capable of ATA 100 transfers. With the lower conductor, you run a higher risk of interference and slower speeds, but it is still just a risk not a certainty.
Your link here helps to prove this belief of mine that old IDE cables that were meant to run with ATA 33 will run with ATA 100 systems at the right speed but with less shielding. I remember reading this somewhere and I thank you for this post which appears to confirm this. Anyone else have something to add?? Please do!
Nice link! After reading the entire article, my theory about the cables seems to be more correct. If you read the second to last paragraph, you'll notice it says:
"without the need for termination devices, new cabling, or other hardware changes,..."
In your first post, your talking about 40- and 80-conductor cables which are exactly identical except that the 80-conductor provides more shielding. Either one is capable of ATA 100 transfers. With the lower conductor, you run a higher risk of interference and slower speeds, but it is still just a risk not a certainty.
Your link here helps to prove this belief of mine that old IDE cables that were meant to run with ATA 33 will run with ATA 100 systems at the right speed but with less shielding. I remember reading this somewhere and I thank you for this post which appears to confirm this. Anyone else have something to add?? Please do!
CyberVenom
Programmer
Although it may be theoretically possible to run ATA/100 over 40 lead (lead, conductor, same thing) cable, I have never been able to accomplish it in an actual test. Perhaps if I were to separate all of the 40 leads so that there is more space between each or shorten the cable to 4 or 5 inces in length, it might work. I'll have to test that. From what I have seen so far, though, if you want ATA/100 (or ATA/66 for that matter) to function at at all instead of immediately reverting to ATA/33, the extra shielding provided by the 80 lead cable is a necessity.
Guest_imported
New member
- Jan 1, 1970
- 0
Well, cdogg, it`s really funny watching you discussion. I just don't understand what are you arguing about? No ATA66 or ATA100 IDE device I have seen in my life (and believe me I have seen a few) is able to operate at full speed (any higher than ATA33) with old, 40 lead cable. Hence 40 lead cables are NOT SUITABLE for ATA66 and above. Just go to your nearest shop and get 80 lead cable (here in Prague, they cost between $2 and $5) for your i815 machine.
Moreover. If you talk about burst rates, well these OPPOSITE of sequential reads. Hence, during sequential read, you will never get eve close to 70 MB/s (with ATA100 drives). On the other hand, when accessing small chunks of data (mainly size that fits into HDs cache), you can get high burst rates of up to 70 MB/s (or more, with new ATA 133 drives).
By the way - most new BIOSes with ATA 66 or ATA 100 support will give warning, or notice, if you connect ATA66/100 capable device via 40 lead cable. So you won`t see anything in windows, but BIOS usualy informs you of this "problem" during post.
Moreover. If you talk about burst rates, well these OPPOSITE of sequential reads. Hence, during sequential read, you will never get eve close to 70 MB/s (with ATA100 drives). On the other hand, when accessing small chunks of data (mainly size that fits into HDs cache), you can get high burst rates of up to 70 MB/s (or more, with new ATA 133 drives).
By the way - most new BIOSes with ATA 66 or ATA 100 support will give warning, or notice, if you connect ATA66/100 capable device via 40 lead cable. So you won`t see anything in windows, but BIOS usualy informs you of this "problem" during post.
lucerben,
Simply not arguing about anything...learning as I go. If you read my first and second post, you'll see that I "asked" this question to paparazi and all who wished to join the conversation.
I understand that 40-lead conductor cables are not recommended if you want to achieve transfers greater than the ATA33 spec. However, it is possible according to the link above. If you've got documentation that says otherwise, don't hesitate to post a link!
I will argue one point. The fastest data transfer rates are achieved when the head's movement is minimized to a sequential read. If you are talking about "small chunks" of data that are placed in "sequential" clusters, then yes I agree with you. However, burst rates and rates from sequential reads are not the opposite. Burst rates will be higher when working with smaller files that are in line, but the transfer rate of one large unfragmented file is still higher than smaller files that are written in different areas of the disk (due to more head movement). I'd like to hear if you disagree.
Sorry for the novel I just wrote! :-V
Simply not arguing about anything...learning as I go. If you read my first and second post, you'll see that I "asked" this question to paparazi and all who wished to join the conversation.
I understand that 40-lead conductor cables are not recommended if you want to achieve transfers greater than the ATA33 spec. However, it is possible according to the link above. If you've got documentation that says otherwise, don't hesitate to post a link!
I will argue one point. The fastest data transfer rates are achieved when the head's movement is minimized to a sequential read. If you are talking about "small chunks" of data that are placed in "sequential" clusters, then yes I agree with you. However, burst rates and rates from sequential reads are not the opposite. Burst rates will be higher when working with smaller files that are in line, but the transfer rate of one large unfragmented file is still higher than smaller files that are written in different areas of the disk (due to more head movement). I'd like to hear if you disagree.
Sorry for the novel I just wrote! :-V
"Just to remind you let us say once again that ATA/100 interface requires the same good old 40-pin IDE cable used in ATA/66. However, since the burst transfer rates have become considerably higher, better protection against crosstalk and electromagnetic noise interference turned out necessary. For this particular purpose 40 additional ground lines were tied together and acted as shields between the lines that actually carried live signals back and forth. So, altogether the new ATA/100 cable is composed of 80 conductors. However, the developers wanted to retain the conventional 40-pin connector, so that to ensure plug compatibility with existing drives and systems. In other words, we can state that ATA/100 has another worthy feature: it is backward compatible with ATA/33 and ATA66 devices, including hard disk drives, removable media disk drives (for example, ZIP, JAZ), CD-ROM drives, CD-R/RW drives, ATA tape drives, and DVD-ROM drives.:
I think they may solve SOME of your questions.
I think they may solve SOME of your questions.
Oops, I forgot this. It is very easy to tell these ribbons apart from normal IDE ribbons. They have a blue connector on one end, a black connector at the opposite end, and a gray connector in the middle. The blue connector <b>must</b> be plugged into the motherboard. The black connector is for master devices, and the gray connector is for slave devices.
Another issue: Transferring a partitioned and formatted hard drive between computers is potentially dangerous if they use different translation schemes INCLUDING moving disk from an old computer that doesn't support translation at all to a new one that does. <b>This is really a little known issue</b>. Another issue has to do with how Windows stores hardware information. Device Manager (Properties of My Computer) holds all driver information for your current hardware. When you take a hard drive that is in a system and move it to a different system, the hardware setup that Windows is holding is no longer valid with the new hardware. When you boot up for the first time after moving the hard drive, you will notice Windows finds all the new hardware. This sometimes isn't a problem, but it most cases it will be. Windows will work fine for a time. After a few days you may notice multiple lock ups at different times. This is most likely caused by a conflict with new and old hardware drivers or possibly a cluttered Windows Registry. If this is what is happening, your best bet would be to completely format the hard drive and install Windows from scratch. That usually guarantees Windows will find your current hardware setup and will not have old drivers or registry keys.
Have fun!
Another issue: Transferring a partitioned and formatted hard drive between computers is potentially dangerous if they use different translation schemes INCLUDING moving disk from an old computer that doesn't support translation at all to a new one that does. <b>This is really a little known issue</b>. Another issue has to do with how Windows stores hardware information. Device Manager (Properties of My Computer) holds all driver information for your current hardware. When you take a hard drive that is in a system and move it to a different system, the hardware setup that Windows is holding is no longer valid with the new hardware. When you boot up for the first time after moving the hard drive, you will notice Windows finds all the new hardware. This sometimes isn't a problem, but it most cases it will be. Windows will work fine for a time. After a few days you may notice multiple lock ups at different times. This is most likely caused by a conflict with new and old hardware drivers or possibly a cluttered Windows Registry. If this is what is happening, your best bet would be to completely format the hard drive and install Windows from scratch. That usually guarantees Windows will find your current hardware setup and will not have old drivers or registry keys.
Have fun!
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