A tip someone gave me on this list.. If your motherboard is UDMA33, you have to disable DMA in bios for that drive. If you check Device manager>Disk drives>properties for your new 66 disk, you may see that the DMA box is unchecked. If you check it, then reboot, it unchecks itself. The only way around it is to disable DMA in bios for that drive. Then it remains checked and you get your speed back Cheers Mat From: Yavuz <yavuz@...> >I have been checking my hard drives with echo utility and I have been >getting strange results.I have two very similar hard drives and they are; >Now from what i know drive 2 ( UDMA66)should perform 30 to 60 % better >than the drive one (UDMA66 ) >Echo utility gives me 37 tracks for Drive one's E: Partition and 29 tracks >for Drive D: