I have a question; I have 3 harddisks and one DVD. I have 2 IDE channels. Of the 3 harddisks, 2 are new and fast, the 3rd is old (and probably slow). How do I optimize the layout?

I have heard that if I have 2 HD on the same IDE channel, then the slowest of them, will set the pace. Hence, a slow HD + a fast HD = 2 slow HD.

I also heard that only one HD can be active at the same time, on one channel. Hence, 2 HD sending data = 1 HD sends data, the other waits.


So how do I do?

Plan A:
Channel 0: fast HD + fast HD
Channel 1: slow HD + DVD


or


Plan B:
Channel 0: fast HD + slow HD
Channel 1: fast HD + DVD





Plan A gives me problem when transferring from fast HD to fast HD, right? Because one of them must wait for the other to finish. If I had Plan B, a fast HD could transfer data to another fast HD, without them waiting.

But fast HD + fast HD keeps up the pace. There is no slow DVD that slows down the data transfer rate.




Plan B gives me problem when transferring data from DVD to the HD on the same channel, but I dont do that often. I would also get problem if slow HD is Pio mode 3 and the fast HD is Pio mode 4, then both would act as Pio mode 3.




So, any suggestions? Please?

IDE works as a chain, but not exactly, that language isn't really condusive to the reality of the situation. Eitehr way will yield the same speeds, I tested this a few times when I worked in a computer shop, You can have it set up like this:

1:
Master: UDMA 133 7200rpm
Slave: DVDrom 100
2:
Master: UDMA 133 7200rpm
Slave: PIO 100 5400rpm

or

1:
Master: UDMA 133 7200rpm
Slave: UDMA 133 7200rpm
2:
Master: DVDrom 100
Slave: PIO 100 5400rpm

And in either case, the read/write speed and access time on all 4 drives should be identical. Using PCMark03(latest at the time I did the tests) Showed scores with 2% on each HD no matter where it was on the chain, or which chain it was on. It was a test we did to check and see, because we had all heard both sides of the story, and wanted to be sure. We tested with Burn n Test as well, which does multiple constant read/writes from drives, and run a few other little tests. We conluded it didn't matter how you had it set up, just make the cabling look nice and easy, cause it didn't matter.

EDIT: After thinking about it, I should mention the CABLE yu use matters a lot. don't use an ATA66 cable on either channel, any channel with something other than a CDrom device you need to be using an ATA133 to allow it full speed.

Ahh! VERY good answer! Thanx a lot!

How do I know if I have an ATA66 cable or an ATA133 cable? I have a 6 month old motherboard with the default IDE cables.



My greatest concern was, the transfer speed when using two fast drives simultaneously. Did you try that? Moving files?

But it seems as the DVD doesnt slow the HD, if you are correct. That would mean I would use Plan B.

Cable type is obvious, if they aren't labelled, then the wider spaced ribbed cable is the ATA66, the one with 2x as many, smaller stridations(cables) is teh ATA133. ATA66 was good in the olden days for HDs, but for the last many years, only DVDs and CDs use them, because they don't move as much data as fast.

And yes, we tried transferring a few files, didn't notice any real difference in file transfer speed either.

kebabbert: Your best option is to add an IDE controller card to your system and only use one hard drive per IDE channel.

My favorite is the Promise Ultra100 TX2 (or Ultra133 TX2), US$25 or so. There are several other IDE controller card options available.

That is not true. ATA-66 and up is 80 wire cable while 40 wire cable is ATA-33.

you coud also just add an ide channel with a pci card.

I forgot to say, Redshirt is correct about hard drive throughput speed does not change but there are exceptions. I found that Maxtor and Seagate drives can not handle sharing a channel. If you have IBM/Hitachi or Western Digital drive with a Seagate drive or Maxtor drive on the same channel, you will notice higher latency and lower throughput. IBM/Hitachi and Western Digital drives does not have sharing problems. kebabbert, if the three drives are either Maxtor and Seagate drives it is best to put them on their own IDE channel. I have not seen any problems when IBM/Hitachi and Western Digital drives sharing one IDE channel.

Oh. Good Forum, this! Thanx!

I will simply suppose I have ATA133 cables, as my motherboard is only 6 months old.

I have
250 GB Maxtor Diamondmax 10, 16MB cache
160 GB Hitachi Deskstar 7K250, 8 MB cache
40 GB Maxtor DiamondMax Plus D740X
Liteon DVD-ROM LTD163


So, I think I will put the largest drives on channel 0, and the rest on channel 1, yes?



Buying a new IDE card would be nice, but I wont do that for now, I think. Thanx for your tip anyway!

Put the Maxtor drives on either channel 0 or 1. Then put the Hitachi drive with the DVD-ROM drive.

you could also us a usb to ide cable or firewire to ide cable and use a super fast bus to onnect one of your drives preferable the dvd but its up to you.