Does it work any better on XP? Could be that the USB drivers don't like your motherboard very much.

Haven't tried XP, but this would also be mostly a Win98 PC. Considered XP first, but in the end I dont see any usecase for XP yet. I will give an update in an hour or so with all the stuff I tested in the meanwhile.

Update:
I did not yet do a full reinstall yet but decided to first experiment further before I break it again with a fresh install. I got the other USB port to work with the mouse. This seemed to be a conflict with the drive controller.
I have a IDE Master: SD Card
Secondary IDE Master: CD Drive
SATA: SSD

Now if I have this on auto, this appears to create a conflict, though all drives are just working fine.
Setting Sata to Legacy, and then Primary Master or Primary Slave deactivates my IDE DRIVE as well as my IDE CD Drive on the other port for some reason.
Setting Sata to Legacy and then Secondary Master or Secondary Slave just deactivates the CD Drive but keeps the Sata SSD active
Setting Sata to Native and then Sata 0 Master , I get the result as in Auto (all drives work, but conflict and USB has issues)
Setting Sata to Native and then Sata 1 Master , the system tries to but, but gets stuck

So I checked what I could test out further. Due to the way the SD Adapter and the CD Drive are situated I can't use a Master / Slave config with a single cable. But now I moved the SSD from SATA 2 to SATA 1. Result: PC Doesnt boot anymore.
I disabled SATA completely. Worked again (without SSD). Back to Auto: Hang. So I tried Legacy-Primary-Master. Weirdly this now turns into just a black screen. Legacy-Primary-Slave: Black Screen. Legacy-Secondary-Master. Works, but no CD Drive. Legacy-Secondary-Slave, also no CD Drive.
Over to Native: SATA0 Master: Hangs, SATA1 Master: Boots, but this is basically the original config, just with different port. So everything works (except for USB) and there is the conflict.
Now the idea was to disable DMA on the SSD to see if the hanging goes away. Weirdly enough the SSD doesnt appear in the system hardware manager (though I can access the data). So I went Legacy-Seconday-Master, to get the drive, disable DMA. Then switch back to Native: SATA0 Master. Nope, Hangs. So I switched it back to DMA.

However, even though both USB ports now work, they do both create the Noise on the SB Live. So I'd still not want to use a USB Mouse. It appears to be vastly reduced by using an additional ground loop noise isolator. But I guess its not the best solution.

I guess I did split this up into two separate issues:
1. The IDE - SATA Conflict affecting USB
2. USB creating Noise

So for now the best solutions I can come up with:
1. Completely remove the SATA SSD
2. Not using a USB Mouse.

But if you have any better ideas I could test, let me know. But I will also now reinstall Win98Se. As some prior USB Driver update killed the graphics driver and I'd rather do it clean. Also I did initially have my SSD Drive visible in Hardware manager...so no idea what happened there...

I moved the SSD over to an IDE connection via Adapter. However, apparently in this case DMA does not work. If you set it to DMA, after reboot the check is gone again. Meaning the Speed is terrible.
The SD Card is at 25 MB s
SSD is at 5MB s (down from 130 MB s)

Next up is to instead putting the IDE CD Drive to SATA. No idea if that works, especially with the CD Audio connection, which was the reason to go for a CD drive in the first place. But in order to test that, I first need to get the rest going, installing all the drivers.

Have you tried muting all analog inputs (Mic, Line-in, CD Audio, etc.) on mixer/Volume Control?
If static noise goes away, you can replace analog CD Audio input via digital S/PDIF connection (CD SPDIF header on SB Live).

ott wrote on 2025-10-15, 05:27:

Have you tried muting all analog inputs (Mic, Line-in, CD Audio, etc.) on mixer/Volume Control?
If static noise goes away, you can replace analog CD Audio input via digital S/PDIF connection (CD SPDIF header on SB Live).

Tried now, muted all (CD Audio, Mic, Line In, TAD In (whatever that is), PC Speaker, CD Digital, Midi Synth) but the issue still occurs. Btw I am using the normal audio out (green) on my SB Live, which I think is a Value version, which also only has SPDIF Out as some plug on the card, not external on the PCI sheet. But never played around with that.

Kordanor wrote on 2025-10-15, 10:34:

Tried now, muted all (CD Audio, Mic, Line In, TAD In (whatever that is), PC Speaker, CD Digital, Midi Synth) but the issue still occurs.

It's possible there's a issue on motherboard side.
I have SB Audigy 2ZS and it also makes static noise on some boards:
Re: i5-3570K / MSI Z77A-G43 / GTX 980Ti / X-Fi Titanium

ott wrote on 2025-10-15, 19:52:

It's possible there's a issue on motherboard side. I have SB Audigy 2ZS and it also makes static noise on some boards: Re: i5-3 […]
Show full quote

Kordanor wrote on 2025-10-15, 10:34:

Tried now, muted all (CD Audio, Mic, Line In, TAD In (whatever that is), PC Speaker, CD Digital, Midi Synth) but the issue still occurs.

It's possible there's a issue on motherboard side.
I have SB Audigy 2ZS and it also makes static noise on some boards:
Re: i5-3570K / MSI Z77A-G43 / GTX 980Ti / X-Fi Titanium

Hrm, possible. Well, I will get a ground loop isolator and see (also get rid of other noise, which is actually audible there, but very faint, but you can hear like "electric noise" when shutting town the PC). But will also longterm use a PS2 mouse then. Just need to find a decent one. I prefer that anyways as I could use a KVM in that case together with an even older machine.

In regards to the SATA SSD... I also tried to use a sata adapter on my CD Drive, so that I have only one IDE lane in use. But something didnt work, mabye the adapter was bad, but also the whole contruction looked scetchy and I had to tape the contacts off. Just something I had lying around here for testing. It didnt work. In any case, I just completely removed the SSD now. The idea was initially to have a "faster drive" as alternative, especially for games going into the XP era.
But I guess the SD Card will do just fine for pretty much everything.

As mentioned previously I am going without the SSD now. Full IDE, no SATA.

But I was still looking in regards to the mouse. I ordered some PS2 compatible USB mice as well as a noise loop isolator.

The noise loop isolater already helps a loot, it makes the noise of the USB mice very very low.

But I then also tested the USB->PS2 mice and ofc they had no noise via PS2, but what surprised me is that both mice I bought also do not have any noise over USB, or noise which is so faint you cant hear it.
What also surprised me, is that it seems like via USB the cursor is generall smoother than via PS2, no matter the mouse. Didnt realize that before. So I decided to actually use one of the new mice via USB and also the ground loop isolator in addition, and that seems to be a pretty good combination.

Tested:
G502 Hero > USB with strong Noise, not PS2 Compatible
G5 -> USB with strong Noise, not PS2 Compatible
Microsoft Basic Optical -> USB with no noise, PS2 Compatible (bought via ebay, not freely available anymore)
CHERRY WheelMouse -> USB with no noise, PS2 Compatible (Amazon ASIN B071VW3582) just 10€, white color fits to retro systems, and seems to be great quality

Noise Isolator I bought is "FeinTech ATG00101"