SCSI vs. IDE

What is the difference, is one better over the other? RPM, Cache, BUffers, etc.

Thnks andrew

Rather than explain myself: http://www.acc.umu.se/~sagge/scsi_ide/

Basically, if you're only getting one device, there's not much advantage of one over the other. If you're getting multiple devices, scsi is better, read for why. Thats why scsi is used a lot for servers, since they have many drives.

SCSI is better for a lot of continuously accessed devices as it offers 55MB/s per drive. That means with 4 drives it can transfer at 220MB/s. IDE is fine for normal pc users. Less expensive and easier to implement. Also worth looking into are SATA (Serial ATA) devices. Basically, they have the best of IDE and the best of SCSI implemented into a standard system.

SATA Buses only support 4 devices in the newest intel systems. AMD support is coming. Currently, most intel/AMD boards only support two devices in conjunction with the standard IDE.

SATA drives at the moment are much cheaper than SCSI and the transfer rates start at ATA150. (the current maximum is ATA133 with the norm being ATA100... 150MB/s vs 133MB/s vs 100MB/s which are all slight variations on the original UltraDMA transfers used in IDE only).
With SATA drives finally hitting 15,000 rpm, they are becoming very appealing as a SCSI alternative. They still dont transfer as fast, but are much cheaper (A 250GB IDE drive costs about $150; SATA drive costs about $200; a SCSI drive half that size will be $400 to $700)

Breakdown:
IDE (7,200 rpm/100-133MB/s)= Standard, cheap, easy
SCSI (10,000-15,000 rpm/up to 55MB/s per drive)= expensive, fastest transfers, most drives
SATA (10,000-15,000 rpm/150MB/s and growing)= more expensive and faster than IDE, relatively easy, pushed to become new standard, offers SCSI goodness on lower budget.

I tried to simplify lots of info into a breif explanation. hope this helps you out.