In this test READ performance was tested with four IDE optical drives connected through Port Multiplier onto a PCI-E 8x SATA controller using four IDE-SATA converters.

Optical drive used for testing:

ASUS DRW-1814BL
with QuieTrack Technology, Lightscribe
DVD - 18x write, 8x rewrite, 16x read
CD - 48x write, 32x rewrite, 48x read

As shown in the Silicon Image control panel applet:

When the Port Multiplier with all the optical drives are connected, all four optical drives appear in Disk Management.

A rather subjective test was conducted, as I couldn't find any suitable application to test simultaneous READ performance:

• Produced four copies of a DVD movie
• Created four directories on the system drive
• Began timer
• Dragged the entire contents of each optical drive into separate directories
• When all the file transfers finished, timer stopped
• Repeat procedure, except with only a single optical drive writing onto the hard drive

Results:

4x Optical drives writing 4.08GB of data onto the hard drive simultaneously took 13m 05s.

Single optical drive writing 4.08GB of data onto the hard drive took 7m 30s.

This test shows that performance is decreased with access multiple drives at the same time through the port multiplier. Of course, this could be due to a variety of reasons. The 256MB of RAM on the test system was obviously not enough to handle accessing all the optical drives at the same time, and slowed the system down to unoperable speeds. It seemed that the port multiplier was having difficulties reading from all the optical drives, as there were many instances in which the drive activity LEDs only flashed on the optical drive connected to the lowest ID on the PM. This caused that particular optical drive to finish copying the fastest. Instead of beginning the transfer all at the same time, I was only able to drag and drop a single DVD at a time. With every drag, system performance decreased, so I ended up spending nearly a minute to finish dragging all the files.