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i have 2 hard drives on one channel. great. but 1 is a 60 gig hd w/ ata 100. the other is a 8 gig maxtor w/ ata66. is that a good idea? will preformance suffer?

no, things will work just fine.
when using only the ATA100 drive, the bus will transfer at ATA100 speeds, when using the ATA66 drive the buss will transfer at ATA66 speeds.

you can read more about stuff in this FAQ:
[url=http://www.cdrlabs.com/phpBB/viewtopic.php?t=3032]What are DMA and UDMA ?
[/url]
there are a few links there to pages that contain plenty of info about all this stuff.

Performance will suffer somewhat if you are trying to access both drives at the same time (e.g. copying from one drive to the other). In this case they have to share the bus and one has to wait while the other completes its transfer. If you want to access both drives at the same time you will get best performance by putting each on its own separate channel.

However, if you are only accessing one drive at a time, which is often the case, then performance won't suffer. Modern drives and controllers support independent device timing, so each drive will use the IDE bus at its own speed and not be limited by the other drive's speed as long as they aren't being accessed at the same time. I think this is what dodecahedron was saying.

cfitz

yep. that is what i meant. thanks cfitz.