Ok going through and looking at the next failure in wine tests I found this one : If you look at the code its: 779 color = getPixelColor(device, 160, 120); 780 red = (color & 0x00ff0000) >> 16; 781 green = (color & 0x0000ff00) >> 8; 782 blue = (color & 0x000000ff); 783 ok(red == 0x00 && green == 0x00 && blue >= 0xfe && blue <= 0xff , 784 "DSTALPHA on frame buffer returned color 0x%08x, expected 0x000000ff\n", color); but in MSDN it says : This value is a 32-bit value used to specify an RGB color or CLR_INVALID Format of the rgb color is : 0x00bbggrr The low-order byte contains a value for the relative intensity of red, the second byte contains a value for green, and the third byte contains a value for blue. The high-order byte must be zero. The maximum value for a single byte is 0xFF. so shouldn't it be something like this: red = color & 0x000000FF; green = ( color & 0x0000FF00 ) >> 8; blue = ( color & 0x00FF0000 ) >> 16; not the what is in the test? because of the following C action expression1 >> shift_value Returns expression1 with its bits shifted to the right by the shift_value. The leftmost bits are replaced with zeros if the value is nonnegative or unsigned. This result is the integer part of expression1 divided by 2 raised to the power of shift_value. If expression1 is signed, then the result is implementation specific. so the test seems to be assigning the wrong values to the RGB.... Correct? chris