So that is on interrupt 11, check in the resources view to see if anything else is on 11.
If the COM and LPT are enabled, disabled then in BIOS and that may reshuffle the resources

Matth79 wrote on 2025-08-27, 14:05:

So that is on interrupt 11, check in the resources view to see if anything else is on 11.
If the COM and LPT are enabled, disabled then in BIOS and that may reshuffle the resources

IRQ11 is used also by integrated graphics card iGPU, IRQ Holder and some PCI bridges:

1    IRQ 11                       Shared                VBE Miniport - Standard PCI Graphics Adapter (VGA)
2    IRQ 11                       Shared                Creative SB Live! Value
3    IRQ 11                       Shared                IRQ Holder for PCI Steering
4    IRQ 11                       Shared                Mostek standardu PCI do PCI-do-PCI
5    IRQ 11                       Shared                Mostek standardu PCI do PCI-do-PCI
6    IRQ 11                       Shared                Mostek standardu PCI do PCI-do-PCI
7    IRQ 11                       Shared                Mostek standardu PCI do PCI-do-PCI

I tried to disable USB, COM and LPT in bios but Win95 still detects these devices - probably because the bios settings do not affect in CSM (Legacy) mode and work only in UEFI mode.

If sound probelm appears while start Win95 then possible mute sound and OS still works.
If sound problem appears while playback MIDI then OS hangs.

P.S. The same sound card works OK in WinXP 32-bit or WinXP 64-bit on this motherboard.

I recorded a video when Win95 starts with a broken sound:
https://youtu.be/Ds9ozxtVE_g

H61 chipset doesn't have native PCI ports, perhaps the issue is in ASMedia PCIe-PCI bridge.

I probably found a solution to the problem with MIDI playing through the OUT port. I changed the PCI Latency option from the default 32 to 64 in hidden bios settings. I had to generate the file cmos.txt using AMISCE Utility, check the offset of PCI latency settings - 02 and using RU.EFI in UEFI Shell I changed the value under Setup UEFI variable:

I test playing and no hangs 😀 Setting latency 160 also helps:

I tried also other values:
96, 128 - hangs
64 - playing MIDI OK but Win95 starting sound broken

I keep testing 😀

Unfortunately - the system still hangs with every latency value when playing MIDI over out port. Values ​​160, 192, 224 - eliminate the appearance of the problem to a minimum. Best value is probably 224 - Win95 hangs after about half an hour of listening MIDI files. At the default value of 32, the system hangs after a few minutes. I did not notice the problem with the broken starting sound.
Summary - I do not want to use a system that works unstable and can hang at a random moment 🙁

I changed the motherboard - now I use Asus B85M-E with Haswell 4 Gen CPU that also has one PCI slot and exactly the same PCIe to PCI bridge ASMEDIA.
By default, there is 8 GB RAM but the system does not want to work. After changing the RAM to one 1 GB module, the system works and there are no problems with the same Sound Blaster Live! card on the default latency 32
I am trying to use a system with more RAM and new problems appears but about it in another thread:
Win95 on Haswell, 8 GB RAM - error Insufficient memory...