Sometimes when using a command such as Grid and looking at the output, some of the actual lines (frame, gridlines) that make up the display will be missing on the screen (not finished rendering)
After shaking the notebook by holding it with the mouse at the corner and just slightly pulling it to make it little bigger or smaller, the display will now finish rendering and any missing parts of the Graphics will show up.
Forcing full rendering can also be achieved by making one extra click of the mouse once anywhere in the notebook.
The Graphics can also be made to fully render by moving another application window over the Mathematica notebook and then removing that application window again, all the time without touching the notebook.
This might make one think it can be a windows/graphics card/monitor issue? Since it looks like a repaint event is needed by the OS.
Using V9, windows 7 64 bit. Intel hardware. ATI Radeon HD 5570 graphics card. (note: On version 8, the same issue is present hence it is not a version 9 specific)
Using Default_8.nb with version 9.
Here is a small example
Grid[{
{
Plot[Sin[x], {x, 0, 2 Pi},
AxesLabel -> {"x", "very very loooooooong"},
ImageSize -> {200, 150}, ImagePadding -> {{50, 20}, {40, 30}}]
},
{
Plot[Sin[x], {x, 0, 2 Pi}, AspectRatio -> 1/3,
AxesLabel -> {"x", "short"}, ImageSize -> {200, 140},
ImagePadding -> {{50, 20}, {40, 30}}]
}
}, Spacings -> {0, 0}, Frame -> All
]
Notice the middle line and the bottom line are missing from the grid. Now Clicking in the code cell once caused it to fully draw. Here is screen shot showing before the click and after the click
