Archived posting to the Leica Users Group, 2001/04/04
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]> Just by using a SCSI PC Card I could significantly increase the > performance of the Nikon LS-2000 (but it's SCSI II and not Ultra). It shouldn't matter what SCSI it is (SCSI II or Ultra). It is limited by how fast the actual scanning happens, and the scanning is far far slower than the SCSI bus. The scan takes as long as the scan takes... What did you switch from? I guess you switched from parallel or USB to SCSI? > It also means that my Iomega Jaz 2 GB is slowed down since it is on the > same SCSI chain and the Iomega does use Ultra SCSI :-( Though IOMega does say they support Ultra SCSI for a Jaz drive, but, it really makes no difference. The media transfer rate of the Jaz drive is so far below even SCSI II, that it will make no difference to how fast the data gets from the Jaz drive to the memory... The maximum sustained transfer rate for the 2G Jaz is 8.7MB/sec. Less than half that of SCSI II... The only time it does burst, is when reading from cache, which isn't very often...and especially not for large files. You don't necessarily slow down the SCSI bus by having slower devices on the bus. It's only the data phase that is run at "SCSI II" or "Ultra" rates, not the negotiation phase. This means that if you have a SCSI I device, and an Ultra device, both will operate at their mad data transfer speed, since the negotiation will be done at the slowest speed, and the negotiation takes an infinitesimal amount of time. All this is like "Urban SCSI Myths"...