I recently installed a system with an AMD quad-core processor and integrated nvidia graphics adapter. As some people saw from my initial posts, I was having USB issues and the system would frequently lock up. I worked around this by among other things, disabling APIC in the BIOS. This resulted in my quad-core only using a single core. This really ticked me off. I had paid for a quad-core system and was only getting single core performance. I wondered about an off hand comment I read somewhere pointing out that AMD had bought ATI. So before I went the route of installing an ATI card I tried using the latest nvidia driver and the one-click driver and just couldn’t get it to work with APIC enabled. So this week I installed an ATI Radeon HD4350 for $40. I’ve been able to enable APIC and now have all four cores working and haven’t had any lock ups. One thing I did lose is compiz, but I can live with that. I think its related to a problem when you use the one-click driver. There are some messages that scroll off the screen during the SuSEconfig step, but glxgears does work after running aticonfig --initial to configure the xorg.conf file for the board. I have seen other posts around forums indicating that they resolved problems by disabling APIC or adding pci=nommconf to the kernel line of menu.lst (which is supposed to do the same as disabling APIC). I don’t know how many of them could be similar to mine, but I wanted to share my experience. I was a little skeptical at first and didn’t want to spend a lot of money in case it didn’t work, But for $40 I got my quad-core system back. I don’t know if the problem was that AMD wasn’t playing well with nvidia or if the nvidia adapter didn’t play with AMD or it was linux related (in a moment of desperation during my install I did try fedora and had lock ups so I came back to SuSE who I’ve used for going on 7 years). I tried using the generic (non-nvidia) driver, the driver from the nvidia linux download site, and the one-click and would experience lock ups on all of them until I disabled APIC. But once I installed the ATI card I was able to enable APIC and get my quad-core box back. This isn’t meant to be a post for ATI or against nvidia. I’m simply passing along my experience in the event it helps someone else.