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primary controller/ i r q problems

ptm asked
Medium Priority
Last Modified: 2010-04-27
i have a conflict in my primary ide controller- i can not change the irq's with out changing the master- however- windows will not let me change- i tried to add more irq's but there arent any to add- i dont have much on my system- what can be my problem- i also can not print- i am getting a bidirectional error- i cant even over ride it- i tried a new cable and it still fails  HELP with detailed message!!!!!!!!!!
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What devices do you have attached currently?
What kind of printer do you have?
Is your CD-Rom attached to your soundcard or the motherboard?
What kind of printer cable are you using?
What IRQ is your LPT1 port attached to?
What IRQ's are your primary and secondary IDE controllers connected to?
What is the nature of the conflict in you primary controller?  Note that you can't have a hard drive connected to the same controller as your CDRom.

The last statement in Patrick's comment is not true.

To save time in solving your problem, it will be helpful to know more about your computer.
Please list the components of your system that might apply.
(Motherboard, CPU, RAM, Hard Drive(s), CD-ROM, Soundcard, etc.)
Please post your autoexec.bat & config.sys files here also.

1) What version of Windows are you running?
2) Is this a newly installed hard drive?



I was under the impression that a hard drive and CD-Rom cannot be using the same IRQ, as it causes severe delays (and even freezes) when trying to access the hard drive.  I was told that it had something to do with the data transfer rate of the CD-Rom, which is not high enough to free the controller for use then the hard drive needs to be accessed.  If this is erroneous information, I apologize profusely to ptm and would appreciate if you could set me straight.  :)



 i have a CTX computer , p5vx-be mainboard, v.34 modem
wavable plug and play sound card, cyberdrive 120d cd-rom- with upgrade, IRQ'S  PRINTER- 07, PCI BUS MASTER 14 AND 15, PRIMARY IDE 14, SECOINDARY 15, OPTI- PLUG AND PLAY 09- OPTI PLUG AND PLAY SS 10,
FLOPPY DISC 06  i have windows 95- no new hardware is on my system- my computer is 1 year old, and i have never changed a thing on it

Patrick, I hope this helps explain it:

"I was under the impression that a hard drive and CD-Rom cannot be using the same IRQ..."

The IRQ is used by the controller.  Any two IDE devices can share one controller port. (master/slave)

"...something to do with the data transfer rate of the CD-Rom, which is not high enough to free the controller for use then the hard drive needs to be accessed."

Data transfer rate depends on the transfer mode which is designed into the device. (PIOx, DMA, etc.)  One device may be faster than another on the same channel, so data transfer rate will be limited for the faster one.
Computer performance can be degraded by connecting two devices of differing transfer rates on the same channel.  That won't cause ptm's problem, however.
Try this:
I think, from the motherboard number you have posted, that your board uses Intel's VX chipset.
If so, you can go here for downloading an upgraded busmaster driver and a PCI bridge fix which should take care of your problem.  See the readme files there:


Let me know how it goes and if you need more.

If you have changed nothing on this system what alerted you to this issue?  What does the os report the hard drive IRQ is conflicting with?  Also what exactly is the problem that your machine doesn't print or/and you have an IRQ conflict.

We need some feedback from you.

Jason Shulenberger is right.
Perhaps your conflict is with something else.  Try this...
remove your sound card, modem if there is one and see if you have the problem.
If the conflict is gone it most likely your sound card.

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