hi, Hardware: core2duo(E8400)/Intel Classic Board DG33FBC / 2x2GB I have been trying to install 5.1x64 for it's longterm support and xen but it just does not install till acpi=off is passed. works with one core after that and does not power off. Install stops at ACPI: PCI Root Bridge [PCI0] (0000:00) below is the reply from intel. ============================================================== Thank you for contacting Intel(R) Technical Support. Regarding your technical question, we regret to inform you that Linux* is not a supported Operating system for the Intel(R) Desktop Board DG33FB. Please review the following list for supported Operating systems for your Desktop Board. http://intel.com/support/motherboards/desktop/sb/CS-008326.htm Intel(R) Technical Support cannot provide assistance or drivers on operating systems that are not supported by the specific motherboard. Also, be aware that Intel(R) Desktop Boards do not support manually changing the IRQs, as the OS usually handles this. You can try disabling the onboard audio to check if you get rid of the POST error message. ============================================================== the dmesg from Centos5.1 install after acpi=off is here http://www.pastebin.ca/1043584 Fedora 9 does not seem to have problem and installs fine. the dmesg is here http://www.pastebin.ca/1043590 Maybe we need to wait for another year or two for upstream and centos to catchup. :) -- rm