Bart Schaefer wrote: > On 5/30/07, Feizhou <feizhou at graffiti.net> wrote: >> Bart Schaefer wrote: >> > We have not tried building a kernel, nor installing any drivers or >> > other kernel-related software other than that available from the >> > CentOS project repos. However, the machine is fully yum-updated. >> >> So you also do not have the IOMMU enabled in your boxes? > > % dmesg | grep -i iommu > Please enable the IOMMU option in the BIOS setup > PCI-DMA: using GART IOMMU. > PCI-DMA: Reserving 64MB of IOMMU area in the AGP aperture Try building a 2.6.21 kernel and see if your problems go away.