XBox - Adjusted laser pot and still no-go; ideas?

[ksignorini]

My 2005 XBox has an SDG-605F in it and it isn't reading discs. I cleaned the laser first. No go. Then, I adjusted the pot from 1247 down to around 560 in increments of about 100-150 at a time, and I've now given up.

Is it possible that I just missed the point at which it will work? (That is, maybe I went to 720 from 850 but it would have worked at 785?)

Any other ideas besides a wholesale swap-out?

Thanks.

[Lina_Inverse_]

There's always the hot swapping HDD method. These videos explain it in detail: 
https://www.youtube.com/watch?v=iV8B6eZVkBM
https://www.youtube.com/watch?v=nbSb7BFRQNo