IRQ conflict - COM1 hogs IRQ 15

[nh39]

Hi,

It's a Dell Latitude D800 laptop, Win XP with a docking station. The problem only occurs when the laptop is docked. There hasn't been any new device added to the computer, recently. At first the printer, which is connected to COM1, suddenly stops working, and now the CD-ROM, which is connected the Secondary IDE, also stops working. In Device Manager, I've found that COM1 is trying to use IRQ 15 instead 3 or 4 as it's supposed to. I've tried to maneuver around the BIOS and Device Manager to fix the problem but can't find a way to change the IRQ settings. Deleted the Docked Profile (hardware profile) but the new profile still comes back with the same problem.
What should I try next? Thank you in advance for any of your help.

 

[nh39]

Called Dell. The tech went through the routine of checking this and that, and eventually decided to send a replacement.

 

[SDMguru]

Hit F2 to get into the Dell BIOS and you can page over to a few options for the Dock. Try disabling COM1 on this page or changing the Cdock/II option regarding multiple docks.

Hope this helps.

BTW Dell outsources all of their tech to the lowest bidder so don't take anybody's word as absolute. Good luck.

 

[nh39]

<b><font color="red">"BTW Dell outsources all of their tech to the lowest bidder so don't take anybody's word as absolute."</b></font>
It's good to know this piece of info. Thanks SDMguru.

I have a D/Dock but will look into it.

 

[SDMguru]

I use the Cdock with a lattitude 610. I have to say in all my years dealing with PC's that the dock problems I have had are the worst.

I had a similar issue as you except my com ports were fine but secondary IDE refused to work properly when docked, or would lock the system.

It's been much better under windows 2000 though.

 

[nh39]

Recieved another D/Dock but the new one couldn't make any difference either. I tried disabling the COM1 but still no luck. Switching the serial port to COM1/2/3/4 didn't help. I also tried to configure the resoures manually; but as soon as I clicked OK, the screen flashed for a brief second showing the Secondar IDE without yellow exclamation mark and then flashed again to go right back to the same old problem. This one is really kicking my butt.

 

[SDMguru]

It sounds like your windows device tree is hosed. Have you tried XP's restore function? If the problem only recently occurred you may be able to restore to before the problem popped up.

I'm afraid that without editing the registry and or modifying/removing INF files your options may be limited to recovery CD or reinstall with repair option.

If you do end up having to re-image your hard drive you can use microsofts files and settings export wizard. This will allow you to export some of your installed programs and all of your tweaks, and personal settings, desktop, email etc and then re-import them to the new install. It's under accessories and I think system tools.

I don't want to say there is no other way to fix it but without having someone very knowledgable having access to your machine to troubleshoot this is the best you are likely to get through a forum. I hope you find that magic answer though.

 

[nh39]

Replaced the motherboard and it fixed the problem.

 

[satrow]

Glad you've sorted it.

I'm using a CdockII with an Inspiron 4100 (that thinks it's a Latitude C610); it's always worked well(up to 4 monitors!); Device Manager looks a nightmare, though - 16 devices sharing IRQ11!

Andy.