Hal,
I tried the PAR: NYUF004 in: fractint.par that uses the formula: Richard1 in: fractint.frm at 1024x768x256. I kept the MaxIter=150 and tried turning Floating Point off and on. ("no/yes") on the X-screen.
"Floating Point=no" (fract001.gif) looks like this: http://tinyurl.com/fract001-No-FP
while "Floating Point=yes" (fract002.gif) look like this: http://tinyurl.com/fract002-Yes-FP
This would be a comparison of integer math to floating pointmath. Try setting debug=90 on the <g> screen. This will switch the floating point math back to the C formula parser. Compare the resulting image to the floating point image with one when debug is not set. The floating point image matches the one generated using floating point under Dos Box. The integer math is suspect at this point. Jonathan