screen locks

[jot027]

i have a p3 733 (@825mhz), pc133 ram, a soyo mobo, and a asus geforce 2pro. When i try to use the asus tweak it never seems to lock the 'new' memory frequency and it always defaults to 400mhz. As well, i replaced my mx with the pro and since then i seem to suffer screen lockups when running dvd's and only dvd's, since the dvd player is asus's windvd i'm looking for some fresh ideas to try to ditch this pain in the ass problem.