I'm thinking about getting a new laptop with Win 10. The only things they offer is

Cinema 3 onboard sound
the reast usb external ones

Games I have are

Tex Murphy
Siberia
Phantasamoria
XII
Still Life
Runaway
Wolfenstein 3D Spear of Destiny
Return to Castle Wolfenstein

Will those games play sound properly?

Unless the usb sound card does something really weird, it should work just fine.

Most of those game you listed are basically expecting Adlib/Sound Blaster bare minimum, which at this point are completely emulated in software, so as long as you can get DOSbox/your master sound pointed at it, it should all run fine.

It should work fine, as Windows will recognise it as a sound card and so it will just use it as it would use any other sound card. The only difference (probably) is that this one will be sticking out of your laptop.

I have been using two USB sound devices (USB headphones and USB speakers) for many many years, and they work with absolutely everything. Even in Windows XP and Windows 98SE, my ancient desktop PC does not even have any real sound card, so those two USB devices are the only way to get sound out of it.

EDIT: And yeah they work great in Linux Mint too, of course.

will work without issues. Even my usb bluetooth headset with included sound card works perfectly fine in any dosbox game.

Sound Blaster X-Fi Go user here (USB sound card though nothing professional or anything like that, looks like a pendrive). Sometimes (really once every few weeks) I have to reconnect the card because it doesn't "boot" and the laptops keeps using the speakers, but after unplugging and replugging it just works without problem. GOG games, Steam, movies, YouTube, everything works with the speakers through the Sound Blaster. Hope it helped! :)

These are the two options for playing GOG games


Integrated HD Audio powered by soundblaster Cinema3 onbound sound

Creative Soundblaster X-FI surround 5.1 pro usb soundcard powered by THX TruStudio

I assume Cinema 3 onboard sound would not be strong enough correct?

Oh yeah, about that... Doesn't the laptop have internal onboard sound (chip) anyway, the Cinema 3 onboard sound? So if you don't want to use USB sound devices, you don't necessarily have to.

I am unsure what "reast USB external ones" is, does it mean USB speakers? In that case I think you have two audio devices in your system, the internal Cinema 3 audio, and Reast USB. You can select yourself within Windows audio options which you want to use, and make it the default one. I am pretty sure the laptop still has normal analog audio ports (audio out, mic) which utilize the onboard sound (Cinema 3).

If you use the USB sound device (be it USB headphones, USB speakers, a USB audio "stick" which has analog audio ports for external speakers or headphones) for your audio, then basically your onboard audio is just not utilized. As I mentioned, my old desktop doesn't even have any sound card, so I use USB speakers and USB headphones with it to get audio in Windows and Linux. The USB devices get recognized as valid sound devices (even in Windows 98SE!).