Sound Blaster Pro compatible, FM has to be emulated with a TSR unfortunatley.

Does it work with all games that use sound blaster or does it have compatibility problems similar to PCI cards?
Just wondering if it is worth paying few euros for MVP4 motherboard that only has pci slots.

Apart from the emulated FM it should be more compatible than PCI Sound Cards that requires a TSR like the Sound Blaster PCI/Live/Audigy and Aureal Vortex. One of the games I like to run when testing compatibility is Pinball Fantasies, it's very picky when it comes to timings and such. I think if you don't mind the lack of a real FM synth you should be find or you can always run a YMF 7x4 PCI, ESS Solo-1 or ALS4000 on that board with good Sound Blaster and FM support.