I read your recent comments regarding the performance of Media Vision's SCSI interface, specifically as they relate to measured CPU utilization levels during sustained data transfers of 150 kB/sec. I would like to share with you the results of tests we have completed here at Media Vision, and which you should be able to duplicate at CompuAdd, and set the record straight. I have listed below both the software and hardware components of the test.
System: Toshiba 3200SXC
CPU: 80386SX 20 MHz
CD Interface: Pro AudioSpectrum with Trantor SCSI device driver
ver. 1.31e
CD-ROM Drive: SONY 6211
Test Program: Microsoft CDSPEED ver. 1.0 (10-14-91)
Date of Test: November 4, 1991
When run on the above system, the results of the test yielded an
average CPU utilization of 37.88 percent for sustained data transfer
rates of 150 kB/sec, well within the compliance levels established for
the MPC.
In addition, the same test performed on a generic IBM PC/AT compatible with an 80286 CPU running at 16 MHz, yielded an average CPU utilization of 38.53 percent. At no time did we measure a CPU utilization spike of 80%, and we most certainly have not experienced any sustained degradation of performance, as may be implied from your comments.
It is my suspicion that a lower performance SCSI CD-ROM drive may have
been used in your test(s), one that does have the same performance
characteristics that have been consistently demonstrated by the SONY
541/6211 (which is included in Media Vision's MPC Upgrade Kit).
I will be glad to supply a complete listing of the full test results for
any and all interested parties, provided they extend the same
