I am not sure either. It seems to have a periodic freeze, say every 10 seconds for example. Just using the file manager seems very sluggish. What G3 card do you have? I have a Sonnet, which unfortunately I haven't figured out a way to disable speculative execution on this one, which I think could help. Maybe I could throw my 450MHz in which does allow me to disable speculative execution and see if that helps. Also, all my RAM slots are filled and inter-leaved, which I believe is often not recommended with G3 upgrades. Lastly, there's a lot more going on I think with the ZULU SCSI compared to your SD to ATA adapter, so perhaps there's an issue there.