There are jumper settings to go back to the 030 on board.. But maybe put the 040 back in and retry a few more times..Hopefully I get my cable in next few days. Over at A1K.org there was similar probs and quote" If necessary, try another Amiga, because that can also be due to a defective CIA. Or because maybe the pin strip is not properly plugged in the plug. So yes, keep trying until it works.
Or it's due to a broken cable - the likelihood is low with a brand new cable, but if you tear it sufficiently strong, you'll break everything. In the case, the wiring plan is public in the wiki; You can use a continuity checker pin by pin to check if the connections are still OK.
Jens "