First time I've heard of this. But I highly doubt the sound effects are any different from what was standard for DOS; according to
Wikipedia stub article for the sound card:
The Thunder Board was an 8-bit mono personal computer integrated circuit sound card from Media Vision, that had Sound Blaster compatibility at a reduced price. <snip> Emulates SB 1.0 and 1.5
Other features included:- 8 Bit mono record and playback of .VOC files
- Yamaha YM3812 OPL2 FM Synth
<snip>
The description sounds like a cheaper knock-off of Sound Blaster, and there's certainly nothing in the hardware specs to suggest it has any capability that would be superior to the Sound Blaster cards available at the time. (The two I included in the quotation above are identical to what Sound Blaster had.)
There's also the matter that I'm not sure anyone still has old enough hardware to confirm what things actually sound like with that sound card. DOSBox doesn't help since its emulation is based on Sound Blaster.
If you manage to get a copy of the disks and are able to dump their contents, we're happy to help with determining whether there are any differences in the files compared to regular versions of DOS Lemmings 1. My guess is no but you never know.
