These old motherboards can be finicky like that.

On my PC Chips M571 there's a memory setting called "C000, 16k Shadow ". By default it's set to "Enabled". However, you can also set it to "Cached" for improved performance. And while that does result in a 3-5% speed boost, any sound cards (integrated or standalone) start crackling while that setting is on.

I was able to get the CDROM working with these settings.
Re: SB CDROM install NOT working.(solved)

Please read all my comments to know how I able to get it to work.

SB ide headers are generally set at the 3rd or 4th IDE channel so I just use this disk:

Joseph_Joestar wrote on 2021-06-07, 18:13:

These old motherboards can be finicky like that.

On my PC Chips M571 there's a memory setting called "C000, 16k Shadow ". By default it's set to "Enabled". However, you can also set it to "Cached" for improved performance. And while that does result in a 3-5% speed boost, any sound cards (integrated or standalone) start crackling while that setting is on.

Yeah, pretty similar to my situation (although not quite).
It really bugs me because I feel like the SB16 is the best fit for this PC, and yet I can't use it. 😅

Just beautiful! Love the photos and hardware condition.

Nick4 wrote on 2021-06-08, 10:03:

Just beautiful! Love the photos and hardware condition.

Thanks, glad you like it! 😀

bloodem wrote on 2021-06-07, 10:25:

But now I have a different problem that I've been trying to debug: I realized that in certain workloads, the SB16 causes VERY lo […]
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But now I have a different problem that I've been trying to debug: I realized that in certain workloads, the SB16 causes VERY loud noises - pops/clicks (with headphones, they can sometimes scare the bejesus out of you).
A few instances where these clicks and pops are always occuring:
- right after MS DOS loads, during the HIMEM extended memory test.
- during 3DBench 1.0C (but much less pronounced compared to the HIMEM test)
- in certain games like Duke Nukem 3D (more rare, but once the pops occur they can be VERY loud).

The pops during the HIMEM testing were a clue, it meant that they are somehow linked to memory. So I tested every possible combination of memory timings / wait states that I could think of, but nothing worked... With the slowest timings and highest wait states the CPU performance drops to DX2-66 levels, but the SB16 noises are still there.
Through trial & error, I eventually I disabled the "memory hidden refresh" option in the BIOS and... the pops completely disappeared. If I enable it back, the noises return. So it's 100% consistently reproducible.
Unfortunately, if I disable hidden refresh, the system is very unstable (it usually freezes within the first 5 - 10 minutes after boot). Tried also toggling slow refresh together with hidden refresh, but the system either remains unstable (with hidden refresh disabled / slow refresh enabled) or with noises (hidden refresh enabled / slow refresh enabled or disabled).

Other things I've tried:
- 3 x SB16 cards (1 x CT2230 / 2 x CT2290), they all exhibit the same issue. Obviously, they work fine on some other motherboards/platforms.
- an ESS AudioDrive ES688 with Yamaha OPL3 (non-PnP) and an ESS AudioDrive ES1688 (non-PnP) - both work perfectly, no clicks and pops.
- an AWE32 CT3980 with Yamaha OPL3 (PnP) - works perfectly, no noises whatsoever (and to my ear it even sounds better than the SB16 cards)
- various 72 pin FPM memory modules (2 x 16 MB, 2 x 4 MB, etc) from multiple manufacturers - no changes with the SB16.
- temporarily switched from VLB I/O & VLB VGA to ISA I/O and ISA VGA, just to make sure that there isn't some weird VLB related quirk at play. Noises are still present, though.

Right now I'm all out of ideas. Seems that this motherboard just hates SB16s but probably works great with any other sound card 😀. Of course, I could use the AWE32 (which would be more period correct for this PC + it's better in every way), but I have other plans for that card...

UPDATE: Problem fixed by.... *drum roll*... moving the SB16 card to another ISA slot. 😁
Now, I know what you're gonna ask: "hey, how come you didn't think of that before?!"
Well, I actually did think about it, I had previously tried slots 5 / 6 / 7 with the same result. But since I now ran out of ideas, I decided to try and move the sound card to the first upper slot (even though this meant I had to do some "wire management" changes. And lo and behold, the annoying clicks and pops have completely disappeared. So weird!
The build is finally done! It now works like I wanted it to.

Pics with the final layout:

That's a great looking system. Have you had a chance to get any gaming done with it?

Oh, yeah! My 5-year-old daughter is actually playing Jazz Jackrabbit on it right now! It runs buttery-smooth with sound at ultra high quality 😁

Sweet! I love when the kids get involved. My son loves his socket A system. We've been playing Sim Coaster and Sim Theme Park this week and he's loving them both

In my house it's against the law for kids to play games of the new millennium 😁 They must grow up with the same games I grew up with!
Damn... I'm turning into my father 😁

Same here. It's funny my son prefers my older games vs the newer kids games

Ha, just randomly google searched for "Targa AT case" and of course somebody on Vogons did a build eventually.

Our first computer was the same Targa AT case model, glad that are still some out there (ours got trashed years ago eventually after rusting in storage for too long).