Here is a quick test of hard disk transfer rates using scsispeed 4.2 (AmigaOS 3.9) and 4.3 (AmigaOS 4.1 Classic). All tests done on the same machine.
Under AmigaOS 3.9 TLSFMem was enabled along with the MAPROM feature of the Cyberstorm PPC and 60ns ram settings to ensure maximum speed.
AmigaOS 4.1 Classic retail version was used with out-of-the-box recommended settings as per the Install guide and FAQ.
The Deneb USB Controller was set to Zorro III mode with DMA enabled under AmigaOS 3.9 and PIO enabled under AmigaOS 4.1 Classic.
Here are the transfer rate results:
And here are the CPU measurements. CPU percentages were obtained using scsispeed’s built in function under AmigaOS 3.9, and CPUInfo.docky was used with AmigaOS 4.1 Classic.