Hi, I have several IBM desktops and some notebooks in which the IDE interface is a SATA controller, most of them Intel. Here's lspci output: ------------- [marcelo.sales@sf002698 ~]$ /sbin/lspci | grep IDE 00:1f.2 IDE interface: Intel Corporation 82801FB/FW (ICH6/ICH6W) SATA Controller (rev 03) ------------- On these machines, I can't enable DMA on IDE devices. hdparm shows: ------------- [marcelo.sales@sf002698 ~]$ /sbin/hdparm /dev/hdc /dev/hdc: IO_support = 0 (default 16-bit) unmaskirq = 0 (off) using_dma = 0 (off) keepsettings = 0 (off) readonly = 0 (off) readahead = 256 (on) HDIO_GETGEO failed: Inappropriate ioctl for device ------------- When I try to enable DMA, I get: ------------- [marcelo.sales@sf002698 ~]$ su -c '/sbin/hdparm -d1 /dev/hdc' /dev/hdc: setting using_dma to 1 (on) HDIO_SET_DMA failed: Operation not permitted using_dma = 0 (off) ------------- I thought this was caused by lack of kernel support for the SATA controller, but I've compiled the FC kernel and the vanilla kernel several times, with different settings, and have got no luck on this. libata is built and loaded, as shown by lsmod: [marcelo.sales@sf002698 ~]$ /sbin/lsmod | grep libata libata 58065 1 ata_piix scsi_mod 129001 3 sg,libata,sd_mod What needs to be done to enable DMA support? I'm using kernel 2.6.16-1.2122_FC5smp. Thanks, Marcelo