Would an old P4 and DDR 400 work nicely as the final speeds are the same, or would the fact that it's quad 100 and 2x200 mean that didn't work out, meaning 266 and 533 would be better as its both base of 133mhz? I know AMD's with 333 fsb and DDR 333 work better, or no worse than (afaik) DDR 400 and 333 FSB, wondering how this might work for P4's.