Grid from TexBoxes is Slow

I've build a prototype custom grid using rows of TextBox controls, but it's
quite slow.  Now if I use a DataGridView, with all my columns as textbox
columns, I imagine all the cells are textboxes as well, and that grid has
huge amounts more functionality than mine.  So, I believe I can greatly
improve the speed of my grid, still using the textbox approach, but I
haven't a clue how.  Some advice would be great.



A question that keeps cropping up in my thoughts is, do I continue
delegating the drawing of borders to the individual textboxes, or do I draw
the grid independently, and place borderless textboxes in the cells.  Is
there even much of a difference?