I'm pretty new to Ubuntu. I installed 7.10 last month and decided to upgrade to 8.04 on my laptop. Everything works great except for some graphics problems. Compiz desktop effects look very choppy and sluggish. Also, xMAME games are sloooooooooow and the audio is very choppy. All of this worked flawlessly under 7.10. What happened?
A few things I've already done: I tried reinstalling the driver by going to System->Administration->Hardware Drivers and unchecking the ATI card, rebooting, checking the ATI card again but that doesn't make a difference. I then installed EnvyNG and allowed it to download the latest ATI driver but it works just as bad.
As a note of interest, without the ATI drivers installed xMAME works perfectly. What's going on here? What should I do next? I'm concerned I may have to revert back to 7.10 because 8.04 doesn't seem as reliable. Any help would be appreciated.