I have a Asus 4870 1gb black knight edition with the big heat pipes on it and some major case fans to keep things cool. Ive got it overclocked using Overdrive from the stock 750mhz to 855mhz and 1050mhz for the memory. However on the bottom of the screen it shows the "Current values" at 500 and 1050. Why is this? Is that really what its running at?