On Wednesday November 6 2002 08:04 am, John Richard Smith wrote:
> Technoslick wrote:
> >I tend to forget as much as I remember anymore, so when Tom Brinkman
> >mentioned the problem was actually stemming from the motherboard's
> > chipset, I remembered reading about that a long time ago. If you
> > are using an older motherboard, especially one that happens to be a
> > cheap brand, there is a chance that applying DMA witll cause a
> > Read-Only device to not work properly or a hard drive to scramble
> > its data.
It's got more to do with the quality and design of the motherboard.
IE, layout design, races (imbeded wiring) and other components, eg,
capacitors, rather than the chipset used (VIA, AMD, Intel, nForce, SiS,
etc.). I know I upset some people by sayin this, but Abit is probly a
good yet popular example of all the above, poor design, poor
implementation, marginal components. OTOH, even a good mobo will have
problems if powered by a marginal power supply.
> Well I guess you have a point because my msi mobo comes with a bios
> setting by default is DMA disabled. I don't suppose they do that for
> nothing.
> So I for one will keep the substance of this discussion stowed away
> at the back of my mind. Just in case.
> John
MSI makes good boards, they're often some of the first ones on AMD's
recommended list. They were the first for 2700+ XP's followed shortly
by Asus and Gigabyte. Similar implied recommendation can be made for
their Intel boards (IMO). For an insite into why DMA is disabled read
down thru /etc/rc.sysinit till you get to "# Turn off DMA on CD-ROMs.
It more often than not...."
The very next section will tell you how to turn it back on,
"# Turn on harddisk optimization ...." IE, uncomment 'USE_DMA=1' and
copy that 'fixed' harddisks file to 'harddiskhd?' for each drive you
want DMA enabled. I always enable it for all drives. I use to do it
with rc.local, but now use the newer method with 'harddisks' as it
catches it earlier in the boot proccess.
--
Tom Brinkman Corpus Christi, Texas
Want to buy your Pack or Services from MandrakeSoft?
Go to http://www.mandrakestore.com
