I have the MSI NX6600GT on a pure 64bit Linux, running fine with the latest nvidia driver, I just had problems with setting up the 32bit compatiblity drivers, seems the system ones were in the way, but couldnt get cedega to work so far, so i cant exactly tell if it really is a problem

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Only stupid thing was... I didnt have the money for a sock 939 CPU and there is no SLI board for sock 734, so...

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the nforce chipset driver are a bit limited (compared to the many feature in winxp), but audio, lan and sata drivers work fine (dont forget to have scsi hard disc support enabled in kernel... seems sata is using the scsi interface in linux)