ata100/udma100

sic_6 · Post by **sic_6** » Mon Jun 18, 2001 12:07 am

i have a udma66 controller on my mobo, and if i get an ata100 drive, will it use DMA to be fast or will it be slow? i know that it will run only 66mb/s either way but is it the SAME actual speed for ata or dma drives? i mean , are teh drives teh SAME access speed? thanks.

edit:also, is it any risk to increase my cdrom's PIO mode from 4 to anything higher? and would it increase speed at all? thanks.

onetrueday · Post by **onetrueday** » Mon Jun 18, 2001 1:12 am

It doesnt matter if you get an ata66 or an older ata100 HD. Both will work with your controller, although it'll be limited to ata66. Just make sure you properly enable DMA by checking the little box. One more note. I personally THINK I see a differance going to ata100, but really there is almost no differance at all. I forgot the actual number, but the REAL speed differant between an ata66 and an ata100 is barely percieved it's so small. Dont think for a moment that you'll actually get 34 more megabytes per second constantly. You might get 10-15 more in burst... not constant. I think the real differance you see is because ata100 enable motherboards have differant north and south brigdes, along with being setup differantly then older ata66 enabled mobos'.

sic_6 · Post by **sic_6** » Mon Jun 18, 2001 2:23 am

what i MEANT was are ata and udmaXX the SAME IN SPEED?

onetrueday · Post by **onetrueday** » Mon Jun 18, 2001 5:10 am

A drive is ata100 and dma enabled. It is not ata100 and udma100.

loosbrew · Post by **loosbrew** » Mon Jun 18, 2001 11:50 am

theoretically they are not the same speeds, though no ide drives can reach a through put of 100 mb/s anyway. so you might notice a little difference in throughout but not much. as far as access time, its up to the particular model drive you get. my maxtor is a turtle compared to my new IbM 60 gxp.

loosbrew