Setting hard drive to dma mode in Windows 7 - Disk Drives (HDD, CD/DVD, Blu-ray) Forum - Disk Drives - Dell Community

Setting hard drive to dma mode in Windows 7

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Setting hard drive to dma mode in Windows 7

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After attempting to run backup using Win 7 backup utility and after reaching 27 percent completion after 22 hours I switched to another backup program (Memo), and it does not seem to be moving much faster. I would like to make sure my hard drives are set to dma. I've done a search and understand the various procedutes using Device Manager, etc. to change to dma if it is not set already. However, I do not get the same screens that the various instructions say should be there. No where is dma mentioned. I've checked this very closely, could be doing something wrong, but I don't think so.

My computer is an xps 9000 running Windows 7.  I've also checked settings on a brand new Inspirion laptop and the settings are the same -- no mention of dma.

Any help will be appreciated.  Thanks.

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  • To the best of my knowledge, there is no such thing as DMA on a SATA interface.  This setting pertains to parallel ATA/IDE drives; for these drives the setting shows up in the Device Manager entry for the drive controller.  I've never seen this on any SATA controller I've looked at.  I'm afraid you will need to look elsewhere for the cause of your problem.

    If you are using DVD's, have you tried another brand?  These disks can be variable in quality, and also, I don't believe the back-up program likes R/W disks, preferring the DVD+ or -R.

    Dell Forum member since 2005

  • Like many others here, I'm still learning, but I never saw a properties box like that on any SATA drive I've had.  Parallel IDE/ATA, yes, but not SATA.  I was wondering about it too until I read Scott Mueller's book on Upgrading and Repairing PCs.  The SATA drive spec requires the drives to emulate parallel IDE drives to include shadow registers for such things as DMA settings for compatibility with IDE drivers native to older OS's.  He states that "many motherboards detect and report a Serial ATA drive as supporting Ultra DMA Mode 5 (ATA/100), which is a parallel ATA mode operating at 100 MBS.  This is obviously incorrect because even the slowest Serial ATA mode (1.5 Gbps) is 150 MBps and Ultra DMA modes simply do not apply to Serial ATA drives."

    Mr. Mueller is an author I have trusted for quite a while, but I'm always willing to re-learn something found to be in error.

    Dell Forum member since 2005

  • Thanks, but like Jack, I can not get to a screen like you show. How about sending specifics on your computer, is it sata, etc?

    I did manage to get to a screen where I've been able to change the external performance to "high" or something like that. I've also changed to Memeo backup software. As a result, the process is going faster, but is still slow. Should have made one change at a time.



  • I took that screen grap from my desktop on a sata drive that's using AHCI with the microsoft msahci driver.

    I had a look after reading the above comments on another pc using the Intel iaStor AHCI driver and couldn't repeat that screen grap. When I ran the Nero Info tool from and looked under configuration the DMA status of both the hdd and optical drive are shown. Hope this helps.

  • I ran the Nero program and went to the same screen as in your post, but can't manage to paste the screen grab. It showed that both internal drives are running in dma mode. Supports udma 0-6 and currently using the same, so I'm assuming dma is not the problem.

    At this point it will take approximately 30 hours to back up about 850 GB. The external HD is connected thru a USB port located at the rear of the computer.Policy is set at Better Performance rather than the dufault Quick Removal. Apparently, this requires that the Safetly Remove Hardware feature must be used to prevent damage?

    Maybe 30 hours is typical?


  • Ah!  You're using an external hard drive via a USB 2.0 port!  That would explain a lot.  The USB 2.0 interface is pretty fast, but it's nothing like an internal drive.  The transfer rate is supposed to be 400 Mbits/sec, or a maximum of about 50 Mbytes/sec.  That is about 1/3 the speed of an internal SATA 1.5 drive.  If you are transferring a lot of data, the back-up will take time.

    Dell Forum member since 2005