Error auto sensing primary master hard disk drive

network16 used Ask the Experts™
I have dell gx 620 desktop, i connected 80 GB IDE Maxtor Hard drive and trying to install Windows Xp but i get a message "error auto sensing primary master hard disk drive " and i am unable to install the windows
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Principal Software Engineer
Try connecting a different disk drive to the system.  If the system sees the other drive, then the problem is in the disk drive and not in the computer.

If the problem is found to be in the disk drive, check the drive select jumpers on the drive.  The drive should be set to "cable select" and attached to the last ("master") connector on the cable.  I have,however, seen a few older Maxtor drives that fail to respond when set to "cable select," but run successfully when set to "master."
This would seem to be more of a hardware issue than a Windows XP issue.

>>  i connected 80 GB IDE Maxtor Hard drive
Is this the only hard drive in the PC replacing a previous one?  Is the IDE cable attached to it properly where the Maxtor can be recognized as the "Master" device?  Is the jumper on the Maxtor set where it's either "Master" or "Cable Select"?


Yes this is the only hard drive connected to the pc. NO the jumper is in different place other than master and cable select. If i have to change the jumper to master or cable select what is the difference between the them.
THe difference is that with "Cable Select" you don't have to worry where you put the data connector on an IDE cable, whether it's in the considered "Master" default position or the remaining "Slave" position.  However, it's not rocket surgery to simply set the jumper to "Master" and then be sure to use the first IDE data connector of the possible two, if there are in fact two data connections off of what you have.  I have been in a Dell that simply had one data connection available to go to a single hard drive.
Steven CarnahanAssistant Vice President\Network Manager

As stated, setting the drive to Master allows you to connect it to any connection on the ribbon cable. However it is common practice today to always connect the master to the end connection. Most computers today come with only a single connection on the ribbon cable, except special orders or servers. The Cable Select setting will work unless you have multiple HDD's connected to one ribbon cable and you want the drive closest to the MB to be the master.
Top Expert 2013

first - you must look  what setting the other drive has; if it has C/S, use the same setting - if set to M, set it also to M
the jumpers can be different on different disk models, here for WD drives :
and here for maxtor :

an explanation of the jumpers :
RojoshoRTCC-III Level-2 Support
Hello Network16,

I have seen this sort of problem before, in the 'old days' :)

First, if the 80GB disk mech is new, some BIOS's need to have the disk mech geometery 'locked' in.  You can do this by going into the BIOS Setup and 'discover' the disk mech - You should see the disk parameters and manufacture.  In fact this is a good first step as if the BIOS does not see the disk mech, then neither will the Windows Install process.

Next, some more details on the difference between 'cable select' (C/S) and 'Master/Slave'.

- With 'Cable Select', the CABLE selects which disk drive is master and which one will be the slave, but there are rules that you MUST follow for C/S to work.
- Using the 'cable select' option is an 'And Gate' affair, meaning that you MUST use a C/S cable AND the jumpers must be set to 'C/S' - any other combination will give you the symptom that you are seeing now.  The choice is yours so long as you have the right cable.

- For 'Cable Select', generally you will see a small hole punched in the ribbon cable, this hole is what separates the ‘masters’ from the ‘slaves’ - But that is not 100% fact as some manufactures will simple not connect the 'control line' at the connector, which you cannot see.  

- In 'most' cases the manufacture will label the female cable connectors with 'Master' and 'Slave' and the other end with 'Motherboard', or 'System Board'.  Additionally, most of the time the ‘last’ connector on the cable is the ‘master’, thus the comments of placing your disk on the last connector – Here is a very crude graphic of what 'most' C/S cables look like:
System        Slave     Master

It is imperative that you use a ‘Cable Select’ cable, when using ‘C/S’.

Again, you must use a ‘straight through’ cable when using the ‘M/S’ option, anything else will give you very strange results.  

Nobus noted some URLs for jumper settings and these should get you on the right path.

Now for troubleshooting thoughts.
1. I am assuming (Yes, I know what happens when one assumes) that this is a ‘new’ disk being introduced to the system – Correct?

If so, then the suggestion of ‘matching’ the jumpers is a very good one, but I am also assuming that the 80GB disks not only new, but is different from the original disk mech – Correct?

If so, and assuming that you have not changed the jumper settings on the original disk mech, then confirming which mode (‘Cable Select’ vs ‘Master/Slave) the original disk mech was using is very important at this stage.  You should be able to confirm the ‘mode’ by comparing the actual jumper settings to the label on the disk mech.

In ‘most’ cases there is one setting where the jumper is either not present or is in a position that is not on the disk mech label.  Having the jumper span to adjacent ‘jumper pairs’ is the same as not having the jumper installed.  It allows the user to ‘store’ the jumper in case they need one in the future.  You will have to check the label to see what a ‘no jumper’ means.  In most cases, this option selects a ‘master’ but ‘no slave’.

?Can you give us a little more details as the orgin of the 80GB disk mech and was it the orginal mech.


RojoshoRTCC-III Level-2 Support

Thank you and good hunting...

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