Re: DMA ?

Tech-Archive recommends: Repair Windows Errors & Optimize Windows Performance

Scientific wrote:
Hello all,

I have an AMD Athlon 64 CPU and SATA motherboard with a separate PCI IDE controller card installed. My BIOS doesn't recognize the controller card (Ultra ATA 133 PCI) in the PCI slot, so I can't tell whether the drives (both Seagate 750 GB)connected to the controller card are using DMA mode or not.

Also, Windows does not provide much info on those drives either. Does anyone know how to determine if DMA is on/off on those drives?

-S

They use a pseudo-SCSI layer, for controllers other than the one
provided by the chipset. And that is why the information is hidden.
All the OS knows, is it sends a SCSI CDB to the driver, and the
driver converts the command into things it knows how to do on
the PCI chip.

The best way to tell if DMA is operating, is to benchmark the drives.
If you see 70MB/sec near the beginning of the disk, and 40MB/sec
near the end of the disk, that would be about right for media
(head to platter) limited transfers. If the card was really
in PIO mode, then you'd see a flat line at about 4MB/sec or
so. The PCI bus can manage 110-120MB/sec, so you would not
expect more than that (like if examining burst performance).

http://www.hdtune.com
http://www.simplisoftware.com/Public/index.php?request=HdTach

Paul
.

Relevant Pages

  • Re: 3-4MB/s vinum performance with two Promise PDC20268 UDMA100 controllers
    ... But when adding a second controller card and two more ... >> drives the new array has a terrible write performance. ... >> case it was interrupts causing the slow down, so I set both pci slots ...
    (freebsd-questions)
  • Re: Installing new hard drive (basic questions)
    ... > hardware configuration before without reinstalling Linux. ... > Using a pci controller card ... > Have a 160 gb master drive connected to the primary ide of the pci ...
    (linux.redhat)
  • Re: Is this a good motherboard?
    ... > What on earth can you find to put in more than 3 slots? ... > I mean - if you're buying new, unless you do something pretty specialist ... I have a Soundblaster Audigy 2, an ATA controller card, a Firewire 400/800 ... >> PCI slots??! ...
    (uk.comp.homebuilt)
  • Re: DMA ?
    ... I have an AMD Athlon 64 CPU and SATA motherboard with a separate PCI IDE ... My BIOS doesn't recognize the controller card ... Seagate 750 GB)connected to the controller card are using DMA mode or not. ... Windows does not provide much info on those drives either. ...
    (microsoft.public.windowsxp.hardware)
  • Re: Maximum Hard Drive Size on older Motherboard ?
    ... even if the motherboard bios is probably limited to 120 gb (this is what ... I've been web searching, and LBA-48 related comments come up, but I don't ... get a PCI controller card with it, should add less than $40 and you ... The pci bus may be the limiting factor and newer ...
    (comp.os.linux.hardware)