I need help, performance wall!

[Fguy64]

What could be causing such a difference in number of searched boards?

Myself I do about 460,000 leaf nodes at 7 ply from the start position, with Q turned on. The extra 60,000 might easily be chalked up to move ordering. Without careful examination of your algorithm, my guess is you are not using alphaBeta properly, or you have little or no move ordering.