Advice Needed IRQ conflict with 3 x TBS cards on one PC

[s-band]

I've got 3 cards, a 6903, 6903X and 6983 on an SFF i7-8700 (4 PCI slots) PC running Win 10 Enterprise LTSC 2019. I use 6 instances of Crazyscan, one for each tuner. All seemed OK but sometimes one tuner on a random card would fail to start and often the 6903X would fail to start either of its tuners, take many minutes to start or be very slow in operation. All drivers were updated to the latest. Re-installing the cards would fix it until next boot. An irritating side effect of re-installing was that the tuner numbers would shuffle. It doesn't seem to be a Crazyscan issue as a failed tuner isn't usable with TBS utilities either. The only thing I could see was that one IRQ was shared between 2 TBS cards and the audio card (on-board):



I moved the 6903 to a spare slot and that gave this result:



Now the 6903 and the 6983 behave correctly. However, the 6903X often will not start if another card has been run first after boot. The 6903X usually works if it is started first.

The option to change IRQ is greyed out on device manager and I can't see any options that help in the BIOS. I've searched and there seems to be no sure fire way of setting IRQs now. Many answer that it shouldn't be necessary.

Any ideas, please?

 

[ozumo]

Not ideal but Is there any improvement if the audio controller is disabled?

It may be possible to change the interrupt mode of the TBS cards or audio controller to MSI (Message Signalled Interrupts) but requires the device to support MSI for it to work. Devices assigned to negative IRQs are already using MSI.

https://maxedtech.com/show-devices-by-irq-in-windows/
https://forums.guru3d.com/threads/windows-line-based-vs-message-signaled-based-interrupts.378044/

 

[CrazyCat]

each card have ONE dual demod IC and you can't use two instances Crazyscan on same card (or another app with my StreamReaderEx-BDA). IRQ sharing issues is some from 90's

 

[s-band]

@ozumo Thanks. The guru3d link is very interesting. When I'm feeling courageous, I'll read it more thoroughly and have a go, I'll image the disk first though! Disabling the audio fixes the conflict. Maybe I'll use a cheap USB sound adapter.

@CrazyCat Thanks. I'm sure that way back we had more control of IRQs.
For me, if one CS instance is running, running a scan or blind scan on the second (on the same card) will stop the first (if it is scanning or the demod is running). However, I've often used both tuners on one card by carrying out the scans one at a time and then starting the demods. It's also possible to re-start the stalled demod. Nothing crashes.

 

[dreamsat]

I had the problem that when I wanted to stream to a player with the TBS 6903X, it didn't work. After switching the hardware off and on, it worked until the next time the computer was started. I no longer have this problem with the new driver.
Unfortunately I don't have a solution to your problem.