You may be able to get some idea from two RasterOps adapters that I have, one each of DB-15/DB-15 and DB15/HD-15.

In both cases, the table of switch positions gives:

DIL switch bank 2, all ON.

DIL switch bank 1

1-1 640x480 ON 832x634 OFF 1024x768 OFF 1152x870 ON

1-2 640x480 OFF 832x634 ON 1024x768 ON 1152x870 OFF

1-3 640x480 OFF 832x634 OFF 1024x768 OFF 1152x870 ON

1-4 640x480 OFF 832x634 OFF 1024x768 ON 1152x870 OFF

1-5 640x480 OFF 832x634 OFF 1024x768 OFF 1152x870 ON

1-6 640x480 OFF 832x634 ON 1024x768 OFF 1152x870 OFF

In the absence of an adapter, these are presumably what the bare card needs to achieve. The given switch positions work with a Q950 at 832x634.

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