Buy a sound blaster card for your sound issues. Who knows what your built-in gigabyte motherboard has in terms of driver support.
As for the video, thats a driver issue most likely... or a video card issue.
I would suggest looking at you driver you are using and viewing in Suse 'yast config, hardware' what the setup is and such. Maybe there's a better choice of settings and resolution you can pick.
My suggestion is lower it to barebones resolutoin and see if your speed increases.