After I boot the computer with an Onda USB 1.0 flash drive, I can read and write files to a DIY Newman USB 2.0 external hard drive, but the speed is far too slow, I estimate it's only 1/25 of USB 1.0. When booting with the Super DOS 7.1 boot disk, it can't boot the external hard drive and the system hangs. What can I do to boot it?

