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Amiga computer related discussion => General chat about Amiga topics => Topic started by: ElPolloDiabl on April 05, 2010, 10:24:59 AM

Title: Which one was faster then SCSI or IDE?
Post by: ElPolloDiabl on April 05, 2010, 10:24:59 AM
I had a nice solid Fujitsu drive for my A2000 and it left me with the impression that SCSI drives were faster. I know it depends on the drive, but is any way SCSI had lower latency than IDE?
Title: Re: Which one was faster then SCSI or IDE?
Post by: countzero on April 05, 2010, 10:33:28 AM
SCSI puts less strain on the CPU, so yes you'll notice it feels faster. It really depends on your SCSI controller specification also ...
Title: Re: Which one was faster then SCSI or IDE?
Post by: Karlos on April 05, 2010, 11:33:53 AM
Many SCSI implementations for Amiga were DMA capable, whereas I don't think any IDE ones are. That certainly makes a difference in the overall performance.
Title: Re: Which one was faster then SCSI or IDE?
Post by: scuzzb494 on April 05, 2010, 12:42:54 PM
Cant say I have ever noticed a difference to be honest. I have two external SCSI units on a chain along with my ZIP and CDRom. Prefer external boxes on an internal SCSI card cus they are easy to expand and change. There is only a slight slow down at boot as they talk to each other, but I do like that they are on their own power and cool out of their own box. I have machines like the A4000T that run totally on SCSI and they work fine with the drives inside.

As to the technical issues I don`t know. All I know is what I get from them and they have served me well without fault. Internal IDE's are another matter... have had them fall over no end of times, especially on the 4000ds and towered A1200s. I have a stack here of busted IDE hard drives.... Strangely no broken SCSI drives.

scuzz
http://www.commodore-amiga-retro.com
Title: Re: Which one was faster then SCSI or IDE?
Post by: Zac67 on April 05, 2010, 12:54:12 PM
Back then IDE drives were consumer stuff and (most) SCSI drives enterprise class, meaning SCSIs had a lower access time and possibly higher rotational speeds (=lower rotational latency and higher throughput).
SCSI has slightly more overhead but usually that's not noticeable.
Title: Re: Which one was faster then SCSI or IDE?
Post by: Chrome on April 05, 2010, 02:08:20 PM
Quote from: Karlos;551485
Many SCSI implementations for Amiga were DMA capable


Most of the low-end scsi-controllers were not dma-capable, for example Supra`s. Remember those bytesync and wordsync-controllers that ate up almost all cpu-cycles while transferring data from controllers memory to computers memory.