[RESOLVED] Udma 66 ???

[strupie]

I've heard a lot about the new hard drives that run on the Udma 66 speed mode.

Is this just technically speaking or are these drives really twice as fast as the normal Udma 33 mode ?

I know that most regular motherboards aren't supporting it but if they do, will we need a controller upgrade in windows such as we needed to upgrade the hard drive controller in win95 ?

If anyone has some info ... please tell me because i'm considering to buy the
IBM 22GXP 22GB hard drive.

StRuPiE

[CompuDocs]

Western Digital has some pretty good info on thier site. You will also need a an 80 lead cable (still uses 40 pins, but puts two leads to each pin). It sounds promising.

Charlie

[scoobie]

you can run the drive without the special controller and cable and they are still much faster than the old style hard drives.

stick to the Western Digital or the IBM drive (same drive different label/size, made by Western Digital for IBM) because the have the 2 meg buffer and a higher kilobyte transfer rate than most of the dma/66 drives out now.

If you run without the dma/66 controller make sure to download the util from the hard drive maker that will disable dma/66, otherwise you won't get the full speed increase.

There is a drastic speed increase for the difference between dma/33 and dma/66 without controller, and not as much of a gain as dma/66 without controller to dma/66 with controller so most people have opted not to spend the money on the special controller.

You won't need an OS upgrade as you listed, for the controller. If you buy a controller it will plug into a PCI slot and have special drivers for the controller.

Promise Tech makes a dma/66 controller, get more info at www.promise.com.

More info in general about these new drives can be found at www.storagereview.com.

Good Luck!

[Nick Wightkin]

dont be under the impression, however, that the drive will run at 66 mbytes/sec.

the max bandwith of the whole udma bus is 66 mbytes/sec. so, you can have four hard drives running at 10 mbytes/sec, and the dma contoller isnt the bottleneck. (instead, the bottleneck is the drive itself.)

dma is really cool, because all the processor has to do is set up some parameters on the controller...and the controller moves the data from the drive to ram...this results in less cpu time needed, since the controller does the work.