Speed up your hard drive? I received this from "LangaList" but have not tried it because I am not computer literate enough to be comfortable doing it.
FREE: A *Super* Speed-Up!
Want to speed your hard drive by 15% or more? Reduce the load on your
CPU by up to 40%? All for free? Read on:
A while ago, "Joy" wrote to me and asked:
Hi Fred. Is there any problem enabling DMA mode for the hard
drive in the check box in Device Manager? I have a 13.9Gig, 7200
rpm, UDMA IBM hard drive. Does it make sense that it isn't
checked? --- Joy
Joy was referring to "direct memory access," a way for one part of a
computer to bypass the CPU and take a "short cut" that can
significantly speed operations. In Windows, you can see your hard drive's current DMA settings by right clicking on My Computer, then Properties, then Device Manager, then Disk Drives. Next, click on your hard drive(s)---it may have an opaque name such as "Generic IDE Disk Type 01"---and then click on the Settings Tab. If you have a system of reasonably recent vintage, you'll probably see an *UN*checked DMA option in the dialog box.
Alas, I didn't have much to tell Joy: To tell the truth, although I'd
tweaked and tuned almost every other part of Windows at one point or
another, I'd never really looked into the DMA settings.
Fortunately, Joy didn't stop there. A few days later she wrote again:
Hi Fred. I thought you might appreciate the follow-up on this. A
friend ( Dave Henry) did lots of researching and came up with
some interesting information....
It makes me wonder why my computer wasn't set up this way before
it was shipped. It obviously would be a huge improvement. This
would surely help lots of people who are not using the DMA
setting.
I haven't made the changes on my computer as yet. I hope to have
a tech walk me through it, although when I talked to the techs
about it previously, they passed it off as no big deal, and they
discouraged any changes.---Joy
"Discouraged" is probably too mild a term. In fact, if you try to click the DMA option box in Windows' Device Manager, you get a dire warning to this effect: "Changing this setting may have undesirable effects on your hardware." That's enough to scare off most people. Who wants to trash a hard drive?
But, given Joy's and Dave's information, I was intrigued enough to do
some digging on my own.
Microsoft's KnowledgeBase says in part:
Many people are familiar with the gains to be had from using IDE
hard drives and CD-ROM drives in DMA mode; a typical machine
today will use 40% of the CPU doing hard drive transfers in PIO
mode and use only 25% of the CPU doing hard drive transfers in
DMA mode, on the same hardware.
Hmmmm. That sounds great. But the factory-installed hard drive in my
(almost new) primary system is a Maxtor, and it arrived with the DMA
option not checked; it was not running in DMA mode. So I visited the
Maxtor site and found this (
maxtor.com ):
DMA is a means of data transfer between the device and host
memory without processor intervention. There are two DMA modes,
Single and Multi-Word. Since single word is slower than PIO
mode, no one uses it. It will be ignored here. Multi Word DMA is
used in EISA, VLB, and PCI equipped systems. They are capable of
the very fast transfer rates, utilizing cycle times of 480ns or
faster.
So clearly, Microsoft and Maxtor both agree that DMA is a Good Thing;
and yet the Windows factory settings on my Maxtor drive were NOT to use DMA. What the heck. The next day, right after I'd made the day's full backup (and thus was safe from any data errors that changing the access method might cause), I first ran a hard drive benchmark, then used Device Manager to select DMA mode, and rebooted.
Everything ran fine. In fact, the first thing I did was rerun the hard
drive benchmark---and saw an immediate 15% speed increase.
Since then, I have to say that on long disk operations (loading large
apps, for example), it feels much, much more than just 15% faster. And
I've had no trouble whatsoever.
Dave had even better results: using a synthetic hard drive benchmark,
he had his CPU utilization drop from 98% to 4%.
I've since checked my other systems here, and all my mainline PCs are
DMA-capable; but NONE--- not one!--- was set up to use DMA. I have no
idea why; it makes no sense. (Needless to say, all my DMA-capable systems are now using the DMA option.)
If you want to try DMA mode, visit the vendor's site for the system
and/or the hard drive brand you have; search for information and advice on whether or not to use the DMA option. Or: Your system's BIOS
information may show whether or not your have a DMA-capable drive.
If the answer is clearly yes or no, then stick with what the
manufacturer says. But if the answer is unclear, and if you have a good backup, you might want to give it a try. Supposedly, if your drive doesn't support DMA transfers, nothing bad will happen, and the drive will simply revert to non-DMA mode.
But if it does work, you just might pick up a nontrivial amount of disk speed that you'd paid for, but weren't using!
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