since both your errors involved the hard drive, check those connection again.
Did you do antyhing to the HD? maybe you change some jumpers or something? just put it back as before.
Put another HD and boot from a slyer's CD (so it doesn't try to boot from the HD).. see if that helps.
If it were your modchip, you would get a FRAG instead of that error.
And if you slightly yank the D0 wire and it's still attached, then don't redo it, it's probably fine.