Paolo Supino wrote: > Hi > > I've installed CentOS 5.2 (i386) in a computer with a DG33BU > motherboard ... When I installed it it crashed because of ACPI issues. > Searching Google I found that I need to turn ACPI off in order to > successfully install CentOS, which I did. > After a while I noticed that because of ACPI is off the Linux kernel > finds, initializes and uses only 1 CPU core in the Q6600 quad core CPU > that is installed in this computer :-( > How can I force it to find, initialize and use all the 4 cores in the > computer even if ACPI is off? you might check to see if there's a BIOS update on http://support.intel.com and flash that, as ACPI uses tables in the flash bios to describe the hardware. Intel is pretty good about fixing stuff like this. http://downloadcenter.intel.com/Detail_Desc.aspx?agr=Y&Inst=Yes&ProductID=2780&DwnldID=17260&strOSs=All&OSFullName=All%20Operating%20Systems&lang=eng indeed, the latest BIOS for that board is 0517 (DPP3510J.86A.0517.2009.0107.2203), and there is a fairly extensive list of bugfixes in the release notes http://downloadmirror.intel.com/17260/eng/DP_0517_ReleaseNotes.pdf do read the readme on the flash processes, there are 5 files, you only need the right one for the method you want to use to flash it. http://downloadmirror.intel.com/17260/eng/BIOS%20Update%20Readme.pdf