Slow transfer from SATA II

Question

Slow transfer from SATA II (IDE) drive to 3 SATA II Drives configured as RAID (1). Drives wouldn't format until we installed the OS onto the RAID -- but it wouldn't install completely. We boot from the independent IDE SATA II drive but when we try to then copy files back to the formatted RAID (1) configuration the copying is very slow. Drivers from Tyan are updated (both chipset and SATA RAID) and we have set the drives to various configurations -- BIOS contoll, PIO, and DMA.