What other cards do you have in your machine?

No other sound cards.

Cirrus Logic CL-GD5422 VGA
Goldstar RT-1201 controller card

Try a different I/O card. Try resetting BIOS to default settings.

Is it a pre 1992 486 motherboard? There was a time in the early 90s when many 386 and 486 systems shipped with faulty DMA controllers. If yours is socketted, it may be replacable. Though, I thought it was related more to high DMA.

Anonymous Coward wrote:

Is it a pre 1992 486 motherboard? There was a time in the early 90s when many 386 and 486 systems shipped with faulty DMA controllers. If yours is socketted, it may be replacable. Though, I thought it was related more to high DMA.

It's a 486-VC-HD. From 1992 apparently.

I had an all ISA late 1992 486 with Symphony chipset and a SBPRO2. Digital audio in X-Wing in particular would freeze it. I had to run the game with FM synthesis effects. There was no workaround that I could find. But I only recall X-Wing being a problem.

What CPU you have in there? Did you try to slow the board down or add wait states?

PeterLI wrote:

Try a different I/O card. Try resetting BIOS to default settings.

Tried both.

Jepael wrote:

What CPU you have in there? Did you try to slow the board down or add wait states?

DX/2-66. Haven't tried wait states, wouldn't know what to change it to.

Random question, are you using any memory managers like EMM386 that put the machine into v86 mode?

I have a similar problem with a 486 motherboard that I traced to a faulty keyboard controller. When any attempt to play sound is made, the PC speaker would start beeping and keyboard input would stop responding. It only happened when the machine was in real mode though. If EMM386 was installed and the machine in v86 mode, the problem would be masked for some reason. Swapping the keyboard controller fixed the problem.

While this board does not have a discrete 82C206 DMA controller, it does have a VIA chipset. I have not used VIA's 486 offerings, but I did have DMA problems on their Pentium products.

Vyothric wrote:

Tried both. […]
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PeterLI wrote:

Try a different I/O card. Try resetting BIOS to default settings.

Tried both.

Jepael wrote:

What CPU you have in there? Did you try to slow the board down or add wait states?

DX/2-66. Haven't tried wait states, wouldn't know what to change it to.

Bigger wait states is slower. I think it does not affect DMA though, just IO cycles. The multi IO card does not seem to have ECP parallel port which could take one DMA channel (3 or 1, no idea what would be the default).

Since it's a DX/2-66 the motherboard runs at 33MHz, so usually the ISA bus runs at 8.33 MHz then. That's quite fast but should work. Can you underclock to 25MHz or 20MHz FSB so CPU is 50MHz or 40MHz?

Some motherboard BIOSes let you set the DMA clock rate higher than the standard 5MHz. You might want to check to see if you have this option and what the driver it set at.