java2d opening issues

i'm carrying opening oddities java2d. i know sun.java2d.opengl vm parameter assent 3d acceleration 2d, nonetheless even controlling uncanny issues.

here law tests i ran:

drawing 25x18 map 32x32 pixel tiles jcomponent

image 1 = .bmp format, settlement 2 = .png format

without -dsun.java2d.opengl=true

120 fps controlling .bmp settlement 1

13 fps controlling .png settlement 2

with -dsun.java2d.opengl=true

12 fps controlling .bmp settlement 1

700 fps controlling .png settlement 2

without acceleration, i'm presumption kind mutation holding place each drawimage() i software, pulling down fps extremely box .png. since though, acceleration, law switch (and png indeed performs impossibly faster)?! craziness!

.bmp settlement 1 translated an settlement form type_int_rgb. .png settlement 2 translated an settlement form type_custom. method unchanging speed but opengl acceleration, i have emanate new bufferedimage an settlement form type_int_argb, pull settlement 1 settlement 2 new image.

here law controlling that:

without -dsun.java2d.opengl=true

120 fps controlling .bmp settlement 1

120 fps controlling .png settlement 2

with -dsun.java2d.opengl=true

700 fps controlling .bmp settlement 1

700 fps controlling .png settlement 2

my genuine doubt is, i assume type_int_argb internal settlement form systems platforms? i'm presumption value different. there proceed me internal value i always emanate new bufferedimages border performance?

thanks advance...