Is your rather EXTREME -100MHz CPU underclock killing it somehow? What's the point of underclocking a 233 for playing games? The P2's architecture can't work just like a Pentium if that's what you're thinking.

If it's for Descent going too fast, then patch Descent 😀

The underclock is not for Descent, but there are some games that seem to behave better with it. The bus speeds are kept at the standard 66 Mhz. The multiplier is reduced from 3.5 to 2.

I guess its definitely possible, but I've not heard of any adverse side effects from underclocking. I will see what CPU's I can dig up or borrow to try at their standard clock.

If it is a CPU issue, why only when digital sound is played?

Did you try to reset the PnP configuration data in the BIOS?
Also you could just set your CPU to its usual frequency for tests to exclude it as cause.

If you're underclocking via FSB, on some boards, the clocks of the ISA bus and PCI bus can be tied to it via a divider. If this is the case you might be running the ISA bus so far under spec that it won't work.

Speculation, of course, but something to make sure of.

HAL: I did not mention it, but when I first had the problem, I cleared the CMOS. This defaulted back to the spec setting of 233 Mhz.

Yushatak: In doing the underlock, I stuck with the standard FSB of 66 Mhz. I only changed the multiplier from 3.5 (233 MHz) to 2 (133 Mhz). I specifically stuck with the 66 Mhz to avoid any side affects on the PCI bus. Since the PCI bus runs at 33 MHz, I only assumed that it was tied to the FSB on these early P2 boards.

Going back to my original post, I just don't think there is enough hardware in the system to be a resource conflict. In the good old days, I managed to not have resource conflicts with two serial ports and two parallel ports hogging IRQ's and DMA.

Thanks for the input everyone. I will try a different CPU as leileilol suggests. I am also going to try to beg, borrow or steal a different motherboard.

Charlie

It IS a 440LX though. In my experience, it's not so friendly with underclocking if you go beyond 200mhz.

Agreed on the LX, but the price was right (free). I used to have a different LX board long ago and it was garbage. I actually ebayed a BX board yesterday. Hopefully it will be here in time for the weekend.

Well, I have a LX configured the same way and didn't had such problems.

Freezes with Soundcards are usually not IRQ related, but might show a DMA conflict.
IRQ conflicts don't freeze the system. The technical point behind this is, that if a IRQ is not correctly detected or a wrong routine handles it, you can still press CTRL-ALT-DEL to reboot, since the keyboard handler is still called. A wrong DMA freezes your I/O subsystem, thus stopping your CPU on next I/O access -> CTRL-ALT-DEL will not work.
This behaviour is nicely shown when using cubic player with a misconfigured sound card. Cubic Players renders a sound buffer to memory and starts playback with a DMA transfer, if the buffer is completely played an IRQ occurs so that cubic player can set the new buffer for playback. The new buffer was rendered by software while the first buffer played using DMA.
So on a conflicting DMA cubic player freezes instantly, CTRL-ALT-DEL does not work to restart.
On a conflicting IRQ it will play a short piece of sample buffer and stop. You can exit the player by pressing esc twice (or use ctrl-alt-del to reboot, but why?)
This is a very quick approach to solve such conflicting ressources.

As for the LX board I would check for something that might have been mapped to ISA ressources.
This might be parallel port in ECP mode - disable it.
SMBBus, USB are also candidates, while these just use IRQs.
SMBBus is annoying on early Athlon boards as it usually is set to IRQ9 fixed.

Maybe check if somehow your BIOS was reset or you battery is low, such that some hardware features got enabled again.... (This doesn't require that you have done anything 😉 ).
That is f.e. why I setup my Hard Drives and do not use Auto Detect. Since Auto Detect is Bios default, it will show some auto detection message when it was reset to default somehow.

As for the speed downgrade to 2x of the P2 - I don't think it makes much sense. It is still faster than a fast P1 and less comfortable in enabling/disabling speed related features, as L1/L2, Turbo, FSB etc.

Elianda, Cubic Player freezes the system as well. Not sure what it means yet...

I guess I need to pickup a new CPU and new motherboard to figure out which is causing the problem and take the trial and error approach.

csavko wrote:

Elianda, Cubic Player freezes the system as well.

Throw in detection override parameters until it doesn't freeze anymore. There's extensive help on that when you pass a -h to it

I was never able to find a way to keep cubic player from freezing the machine. I swapped in a 440BX motherboard, using the same cpu, ram and other hardware and the machine is no longer freezing. I guess I have another motherboard for the junk pile.

Any thoughts on what happened? If we settle on a DMA problem, is it possible the DMA controller went bad? Isn't that a little odd that only the DMA controller would have gone bad as they are integrated in the south bridge on modern motherboards?

Well, it can just be an incompatibility with cubic player. Have you tried some different player? XTC-Play f.e. ?