Hello everyone,
I have subscribed to GOG a few days ago, so I'm kind of a newbie :p I already bought Fallout, Unreal, Duke Nukem 3D, Sanitarium (never heard of this game but it looks awesome) Messiah and Earthworm Jim 3D. They all work perfectly... err, except for the last two : the music are all choppy and it ruins everything :( Some things I noticed :
> musics are choppy when I don't/can't move my character (during in-game movies for exemple) but when I start moving, the problem stops (and if I stop moving, same problem)
> when I open the task manager during the game (by pressing CTRL+ALT+DEL) I go back to the desktop and I can still hear the music, but it sounds perfect here. When I go back to the game, musics are still choppy...
> and now, I think it might be the reason why there's a problem : both games have a "Music" folder and all the files are .ogg files... I downloaded libvorbis.dll and put it in my c:/windows/system32 folder but it doesn't change anything... I downloaded a player that can read .ogg files (Winamp) but nothing as well, in-game music is still choppy... I tried to lower the hardware acceleration for the sound (thanks to Ralackk who quicky answered me on the Messiah forum) but same thing...
So, any ideas ? Did anyone encountered the same problem ? I am using Windows XP... If anyone can help me, I'd be very thankful :)

Sounds like the motherboard battery is dead. You can replace it though. But I've got no idea how much that would set you back - I've never had to replace it.
Getting a new computer would certainly solve many woes. There's no doubt about that. But really it would depend on your budget as to what's the most practical way forward, if that's something you really want to do (and clearly you're going to have to consider it at some point).
I'd recommend building it yourself. Or if you're really uncomfortable with that idea, get someone reliable to do if for you. It would save you money and result in a system that's far more appropriate for your needs.

2-3 €, at most.