olaf@pc:~$ sudo hdparm /dev/hda7

/dev/hda7:
 multcount    =  0 (off)
 IO_support   =  0 (default 16-bit)
 unmaskirq    =  0 (off)
 using_dma    =  0 (off)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 geometry     = 19457/255/63, sectors = 102719547, start = 161276598
olaf@pc:~$ sudo hdparm -Tt /dev/hda7

/dev/hda7:
 Timing cached reads:   786 MB in  2.00 seconds = 392.50 MB/sec
 Timing buffered disk reads:    8 MB in  3.38 seconds =   2.37 MB/sec
olaf@pc:~$ sudo hdparm -d1 /dev/hda7

/dev/hda7:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Invalid argument
 using_dma    =  0 (off)